diff --git a/htroot/yacysearchtrailer.html b/htroot/yacysearchtrailer.html
index 4c10663af..631846e52 100644
--- a/htroot/yacysearchtrailer.html
+++ b/htroot/yacysearchtrailer.html
@@ -190,23 +190,14 @@ function toggleVisibility(name, count) {
 <script>if (#[count]# <= 8) toggleVisibility('namespace', #[count]#);</script>
 #(/nav-namespace)#
 
-#(nav-authors)#::
+#{navs}#
 <ul class="nav nav-sidebar menugroup">
-<li style="cursor: pointer; cursor: hand;"><h3 onclick="toggleVisibility('authors', #[count]#);">Author [#[count]#] <span style="float:right" id="chevron-authors" class="glyphicon glyphicon-chevron-down" title="click to expand facet"></span></h3></li>
+<li style="cursor: pointer; cursor: hand;"><h3 onclick="toggleVisibility('#[name]#', #[count]#);">#[displayname]# [#[count]#] <span style="float:right" id="chevron-#[name]#" class="glyphicon glyphicon-chevron-down" title="click to expand facet"></span></h3></li>
 #{element}#
 <li style="display:none" id="#[id]#"><a href="#[url]#" class="MenuItemLink"><input type="checkbox" onchange="window.location.href='#[url]#'"#(on)# checked="checked"::#(/on)#/> #[name]# (#[count]#)</a></li>
 #{/element}#</ul>
-<script>if (#[count]# <= 8) toggleVisibility('authors', #[count]#);</script>
-#(/nav-authors)#
-
-#(nav-collections)#::
-<ul class="nav nav-sidebar menugroup">
-<li style="cursor: pointer; cursor: hand;"><h3 onclick="toggleVisibility('collections', #[count]#);">Collection [#[count]#] <span style="float:right" id="chevron-collections" class="glyphicon glyphicon-chevron-down" title="click to expand facet"></span></h3></li>
-#{element}#
-<li style="display:none" id="#[id]#"><a href="#[url]#" class="MenuItemLink"><input type="checkbox" onchange="window.location.href='#[url]#'"#(on)# checked="checked"::#(/on)#/> #[name]# (#[count]#)</a></li>
-#{/element}#</ul>
-<script>if (#[count]# <= 8) toggleVisibility('collections', #[count]#);</script>
-#(/nav-collections)#
+<script>if (#[count]# <= 8) toggleVisibility('#[name]#', #[count]#);</script>
+#{/navs}#
 
 #{nav-vocabulary}#
 <ul class="nav nav-sidebar menugroup">
diff --git a/htroot/yacysearchtrailer.java b/htroot/yacysearchtrailer.java
index 2481097dc..6b569f2ef 100644
--- a/htroot/yacysearchtrailer.java
+++ b/htroot/yacysearchtrailer.java
@@ -19,6 +19,9 @@
 // along with this program; if not, write to the Free Software
 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
 import java.text.ParseException;
 import java.util.AbstractMap;
 import java.util.Date;
@@ -41,6 +44,7 @@ import net.yacy.peers.graphics.ProfilingGraph;
 import net.yacy.search.EventTracker;
 import net.yacy.search.Switchboard;
 import net.yacy.search.SwitchboardConstants;
+import net.yacy.search.navigator.StringNavigator;
 import net.yacy.search.query.QueryParams;
 import net.yacy.search.query.SearchEvent;
 import net.yacy.search.query.SearchEventCache;
@@ -223,90 +227,6 @@ public class yacysearchtrailer {
             if (pos == 1 && neg == 0) prop.put("nav-languages", 0); // this navigation is not useful
         }
 
-        // author navigators
-        if (theSearch.authorNavigator == null || theSearch.authorNavigator.isEmpty()) {
-            prop.put("nav-authors", 0);
-        } else {
-            prop.put("nav-authors", 1);
-            navigatorIterator = theSearch.authorNavigator.keys(false);
-            int i = 0, pos = 0, neg = 0;
-            String nav, rawNav;
-            while (i < QueryParams.FACETS_STANDARD_MAXCOUNT && navigatorIterator.hasNext()) {
-                name = navigatorIterator.next().trim();
-                count = theSearch.authorNavigator.get(name);
-                if (count == 0) break;
-                nav = (name.indexOf(' ', 0) < 0) ? "author%3A" + name : "author%3A%28" + name.replace(" ", "+") + "%29";
-                /* Avoid double percent encoding in QueryParams.navurl */
-                rawNav = (name.indexOf(' ', 0) < 0) ? "author:" + name : "author:(" + name.replace(" ", "+") + ")";
-                if (theSearch.query.modifier.author == null || !theSearch.query.modifier.author.contains(name)) {
-                    pos++;
-                    prop.put("nav-authors_element_" + i + "_on", 1);
-                    prop.put(fileType, "nav-authors_element_" + i + "_modifier", nav);
-                } else {
-                    neg++;                    
-                    prop.put("nav-authors_element_" + i + "_on", 0);
-                    prop.put(fileType, "nav-authors_element_" + i + "_modifier", "-" + nav);
-                    nav="";
-                    rawNav = "";
-                }
-                prop.put(fileType, "nav-authors_element_" + i + "_name", name);
-                /* URL is already percent encoded : no need to re-encode specifically for the file type */
-                prop.put("nav-authors_element_" + i + "_url", QueryParams.navurl(fileType, 0, theSearch.query, rawNav, false).toString());
-                prop.put(fileType, "nav-authors_element_" + i + "_id", "authors_" + i);
-                prop.put("nav-authors_element_" + i + "_count", count);
-                prop.put("nav-authors_element_" + i + "_nl", 1);
-                i++;
-            }
-            prop.put("nav-authors_element", i);
-            prop.put("nav-authors_count", i);
-            i--;
-            prop.put("nav-authors_element_" + i + "_nl", 0);
-            if (pos == 1 && neg == 0) {
-                prop.put("nav-authors", 0); // this navigation is not useful
-            }
-        }
-
-        // collection navigators
-        if (theSearch.collectionNavigator == null || theSearch.collectionNavigator.isEmpty()) {
-            prop.put("nav-collections", 0);
-        } else {
-            prop.put("nav-collections", 1);
-            navigatorIterator = theSearch.collectionNavigator.keys(false);
-            int i = 0, pos = 0, neg = 0;
-            String nav, rawNav;
-            while (i < QueryParams.FACETS_STANDARD_MAXCOUNT && navigatorIterator.hasNext()) {
-                name = navigatorIterator.next().trim();
-                count = theSearch.collectionNavigator.get(name);
-                if (count == 0) break;
-                nav = "collection%3A" + name;
-                /* Avoid double percent encoding in QueryParams.navurl */
-                rawNav = "collection:" + name;
-                if (theSearch.query.modifier.collection == null || !theSearch.query.modifier.collection.contains(name)) {
-                    pos++;
-                    prop.put("nav-collections_element_" + i + "_on", 1);
-                    prop.put(fileType, "nav-collections_element_" + i + "_modifier", nav);
-                } else {
-                    neg++;                    
-                    prop.put("nav-collections_element_" + i + "_on", 0);
-                    prop.put(fileType, "nav-collections_element_" + i + "_modifier", "-" + nav);
-                    nav="";
-                    rawNav = "";
-                }
-                prop.put(fileType, "nav-collections_element_" + i + "_name", name);
-                /* URL is already percent encoded : no need to re-encode specifically for the file type */
-                prop.put("nav-collections_element_" + i + "_url", QueryParams.navurl(fileType, 0, theSearch.query, rawNav, true).toString());
-                prop.put(fileType, "nav-collections_element_" + i + "_id", "collections_" + i);
-                prop.put("nav-collections_element_" + i + "_count", count);
-                prop.put("nav-collections_element_" + i + "_nl", 1);
-                i++;
-            }
-            prop.put("nav-collections_element", i);
-            prop.put("nav-collections_count", i);
-            i--;
-            prop.put("nav-collections_element_" + i + "_nl", 0);
-            if (pos == 1 && neg == 0) prop.put("nav-collections", 0); // this navigation is not useful
-        }
-
         // topics navigator
         final ScoreMap<String> topicNavigator = theSearch.getTopicNavigator(TOPWORDS_MAXCOUNT);
         if (topicNavigator == null || topicNavigator.isEmpty()) {
@@ -545,6 +465,68 @@ public class yacysearchtrailer {
             prop.put("nav-vocabulary", 0);
         }
 
+        // navigator plugins
+        int ni = 0;
+        for (String naviname : theSearch.navigatorPlugins.keySet()) {
+
+            StringNavigator navi = theSearch.navigatorPlugins.get(naviname);
+            if (navi.isEmpty()) {
+                continue;
+            }
+
+            prop.put("navs_" + ni + "_displayname", navi.getDisplayName());
+            prop.put("navs_" + ni + "_name", naviname);
+            prop.put("navs_" + ni + "_count", navi.size());
+
+            navigatorIterator = navi.keys(false);
+            int i = 0, pos = 0, neg = 0;
+            String nav, rawNav;
+            while (i < QueryParams.FACETS_STANDARD_MAXCOUNT && navigatorIterator.hasNext()) {
+                name = navigatorIterator.next();
+                count = navi.get(name);
+                if (count == 0) {
+                    break;
+                }
+                String encname = ((name.indexOf(' ', 0) < 0) ? name : "(" + name + ")");
+                try {
+                    nav = URLEncoder.encode(navi.getQueryModifier() + encname, StandardCharsets.UTF_8.name());
+                } catch (UnsupportedEncodingException ex) {
+                    nav = "";
+                }
+
+                rawNav = navi.getQueryModifier() + encname;
+                boolean isactive = navi.modifieractive(theSearch.query.modifier, name);
+                if (!isactive) {
+                    pos++;
+                    prop.put("navs_" + ni + "_element_" + i + "_on", 1);
+                    prop.put(fileType, "navs_" + ni + "_element_" + i + "_modifier", nav);
+                } else {
+                    neg++;
+                    prop.put("navs_" + ni + "_element_" + i + "_on", 0);
+                    prop.put(fileType, "navs_" + ni + "_element_" + i + "_modifier", "-" + nav);
+                    nav = "";
+                    rawNav = "";
+                }
+                prop.put(fileType, "navs_" + ni + "_element_" + i + "_name", navi.getElementDisplayName(name));
+                // URL is already percent encoded : no need to re-encode specifically for the file type
+                prop.put("navs_" + ni + "_element_" + i + "_url", QueryParams.navurl(fileType, 0, theSearch.query, rawNav, false).toString());
+                prop.put(fileType, "navs_" + ni + "_element_" + i + "_id", naviname + "_" + i);
+                prop.put("navs_" + ni + "_element_" + i + "_count", count);
+                prop.put("navs_" + ni + "_element_" + i + "_nl", 1);
+                i++;
+            }
+            prop.put("navs_" + ni + "_element", i);
+            prop.put("navs_" + ni + "_count", i);
+            i--;
+            prop.put("navs_" + ni + "_element_" + i + "_nl", 0);
+            if (pos == 1 && neg == 0) {
+                prop.put("navs_" + ni, 0); // this navigation is not useful
+            }
+
+            ni++;
+        }
+        prop.put("navs", ni); // navigatior plugins - eof
+
         // about box
         final String aboutBody = env.getConfig("about.body", "");
         final String aboutHeadline = env.getConfig("about.headline", "");
diff --git a/source/net/yacy/search/navigator/Navigator.java b/source/net/yacy/search/navigator/Navigator.java
new file mode 100644
index 000000000..20acd21c9
--- /dev/null
+++ b/source/net/yacy/search/navigator/Navigator.java
@@ -0,0 +1,96 @@
+/**
+ * Navigator.java
+ * (C) 2016 by reger24; https://github.com/reger24
+ *
+ * This is a part of YaCy, a peer-to-peer based web search engine
+ *
+ * LICENSE
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ * If not, see <http://www.gnu.org/licenses/>.
+ */
+package net.yacy.search.navigator;
+
+import java.util.List;
+import java.util.Map;
+import net.yacy.cora.sorting.ReversibleScoreMap;
+import net.yacy.cora.sorting.ScoreMap;
+import net.yacy.kelondro.data.meta.URIMetadataNode;
+import net.yacy.search.query.QueryModifier;
+
+/**
+ * Interface for search navigators used in search servlets to restrict displayed
+ * search results.
+ */
+public interface Navigator extends ScoreMap<String> {
+
+    /**
+     * @return name of the navigator for display in ui
+     */
+    public String getDisplayName() ;
+
+    /**
+     * Display form of the element (e.g. for languages the key might be "en",
+     * the display form "English"
+     * 
+     * @param key original key as counted in this navigator
+     * @return a translated display text for a key
+     */
+    public String getElementDisplayName(String key) ;
+
+    /**
+     * Returns the query modifier prefix. This is used (needed) within the servlet
+     * to create a new modifier for a activated (clicked) navigator item.
+     *
+     * @return the query modifier prefix (if any, eg. "filetype:" or "author:" )
+     */
+    public String getQueryModifier() ;
+
+    /**
+     * Add counts for this navigator from documents in the provided list.
+     * The navigator looks for a field in the document and increases the counts
+     * depending on the value in the document field.
+     *
+     * @param docs list of documents
+     */
+    public void incDocList(List<URIMetadataNode> docs);
+
+    /**
+     * Add count for this navigator from provided Solr facet map.
+     * The navigator looks for a field in the facet map and increases the counts
+     * by the value in the facet map.
+     *
+     * @param facets Solr facets
+     */
+    public void incFacet(Map<String, ReversibleScoreMap<String>> facets);
+
+    /**
+     * Add count for this navigator from provided document.
+     * The navigator looks for a field in the document and increases the counts
+     * depending on the value in the document field.
+     *
+     * @param docs document
+     */
+    public void incDoc(URIMetadataNode doc);
+
+    /**
+     * Helper routine to determine if current navigator key is part of the query
+     * modifier (is active)
+     *
+     * @param modifier current search query modifier
+     * @param name the navigator key to check
+     * @return true if navigator key is mentioned as modifier
+     */
+    public boolean modifieractive(QueryModifier modifier, String name);
+}
diff --git a/source/net/yacy/search/navigator/RestrictedStringNavigator.java b/source/net/yacy/search/navigator/RestrictedStringNavigator.java
new file mode 100644
index 000000000..af3a6aa12
--- /dev/null
+++ b/source/net/yacy/search/navigator/RestrictedStringNavigator.java
@@ -0,0 +1,108 @@
+/**
+ * RestrictedStringNavigator.java
+ * (C) 2016 by reger24; https://github.com/reger24
+ *
+ * This is a part of YaCy, a peer-to-peer based web search engine
+ *
+ * LICENSE
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ * If not, see <http://www.gnu.org/licenses/>.
+ */
+package net.yacy.search.navigator;
+
+import java.util.HashSet;
+import java.util.Set;
+import net.yacy.cora.sorting.ScoreMap;
+import net.yacy.search.schema.CollectionSchema;
+
+/**
+ * A Navigator that allows to restrict the items
+ * If allowed items are set only these will be counted or displayed
+ * If forbidden items are set these are excluded from display
+ */
+public class RestrictedStringNavigator extends StringNavigator implements Navigator {
+
+    Set<String> allowed; // complete list of keys, if empty all keys are allowed
+    Set<String> forbidden; // keys to exclude
+
+    public RestrictedStringNavigator(String title, CollectionSchema field) {
+        super(title, field);
+        this.allowed = new HashSet<String>();
+        this.forbidden = new HashSet<String>();
+    }
+
+    /**
+     * Add a allowed navigator key string. If set, only allowed items are displayed
+     * which means you have to add all possible key which sall be allowed.
+     *
+     * @param s key
+     * @return true if added, false if already existed
+     */
+    public boolean addAllowed(String s) {
+        return this.allowed.add(s);
+    }
+
+    /**
+     * Add a blacklisted item which shall be excluded from counting and display.
+     *
+     * @param s key
+     * @return true if added, false if already existed
+     */
+    public boolean addForbidden(String s) {
+        return this.forbidden.add(s);
+    }
+
+    /**
+     * Increase counter if item allowed and not forbidden
+     * @param key
+     */
+    @Override
+    public void inc(final String key) {
+        if (!forbidden.contains(key)) {
+            if (allowed.isEmpty()) {
+                super.inc(key);
+            } else if (allowed.contains(key)) {
+                super.inc(key);
+            }
+        }
+    }
+
+    /**
+     * Increase counter if item allowed and not forbidden
+     * @param key
+     */
+    @Override
+    public void inc(ScoreMap<String> map) {
+        if (map == null) {
+            return;
+        }
+        for (String entry : map) {
+            if (!forbidden.contains(entry)) {
+                if (allowed.isEmpty()) {
+                    int count = map.get(entry);
+                    if (count > 0) {
+                        this.inc(entry, count);
+                    }
+                } else if (allowed.contains(entry)) {
+                    int count = map.get(entry);
+                    if (count > 0) {
+                        this.inc(entry, count);
+                    }
+                }
+            }
+        }
+    }
+
+}
diff --git a/source/net/yacy/search/navigator/StringNavigator.java b/source/net/yacy/search/navigator/StringNavigator.java
new file mode 100644
index 000000000..a3049cddd
--- /dev/null
+++ b/source/net/yacy/search/navigator/StringNavigator.java
@@ -0,0 +1,141 @@
+/**
+ * Navigator.java
+ * (C) 2016 by reger24; https://github.com/reger24
+ *
+ * This is a part of YaCy, a peer-to-peer based web search engine
+ *
+ * LICENSE
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ * If not, see <http://www.gnu.org/licenses/>.
+ */
+package net.yacy.search.navigator;
+
+import java.util.Date;
+import java.util.List;
+import java.util.Map;
+import net.yacy.cora.federate.solr.SolrType;
+import net.yacy.cora.sorting.ConcurrentScoreMap;
+import net.yacy.cora.sorting.ReversibleScoreMap;
+import net.yacy.kelondro.data.meta.URIMetadataNode;
+import net.yacy.search.query.QueryModifier;
+import net.yacy.search.schema.CollectionSchema;
+
+/**
+ *
+ */
+public class StringNavigator  extends ConcurrentScoreMap<String> implements Navigator {
+
+    public String title;
+    public CollectionSchema field;
+
+    public StringNavigator(String title, CollectionSchema field) {
+        super();
+        this.title = title;
+        this.field = field;
+    }
+
+    @Override
+    public String getDisplayName() {
+        return title;
+    }
+
+    @Override
+    public String getElementDisplayName(String e) {
+        return e;
+    }
+
+    @Override
+    public String getQueryModifier() {
+        String mod;
+        if (field != null) {
+            switch (field) {
+                case author_sxt:
+                    mod = "author:";
+                    break;
+                case url_protocol_s:
+                    mod = "/";
+                    break;
+                case url_file_ext_s:
+                    mod = "filetype:";
+                    break;
+                case collection_sxt:
+                    mod = "collection:";
+                    break;
+                case host_s:
+                    mod = "site:";
+                    break;
+                case language_s:
+                    mod = "/language/";
+                    break;
+                default:
+                    mod = ":";
+            }
+        } else {
+            mod = ":";
+        }
+        return mod;
+    }
+
+    @Override
+    public void incDocList(List<URIMetadataNode> docs) {
+        if (field != null) {
+            for (URIMetadataNode doc : docs) {
+                incDoc(doc);
+            }
+        }
+    }
+
+    @Override
+    public void incFacet(Map<String, ReversibleScoreMap<String>> facets) {
+        if (field != null && facets != null && !facets.isEmpty()) {
+            ReversibleScoreMap<String> fcts = facets.get(field.getSolrFieldName());
+            if (fcts != null) {
+                this.inc(fcts);
+            }
+        }
+    }
+
+    @Override
+    public void incDoc(URIMetadataNode doc) {
+        if (field != null) {
+            if (field.getType() == SolrType.date) {
+                Date dd = (Date) doc.getFieldValue(field.getSolrFieldName());
+                String year = Integer.toString(dd.getYear() + 1900);
+                this.inc(year);
+            } else {
+                Object val = doc.getFieldValue(field.getSolrFieldName());
+                if (val instanceof List) {
+                    List<String> ll = (List) val;
+                    for (String s : ll) {
+                        this.inc(s);
+                    }
+                } else {
+                    if (val != null) {
+                        this.inc((String) val);
+                    }
+                }
+            }
+        }
+    }
+
+    @Override
+    public boolean modifieractive(QueryModifier modifier, String name) {
+        if (name.indexOf(' ') < 0) {
+            return modifier.toString().contains(getQueryModifier() + name);
+        } else {
+            return modifier.toString().contains(getQueryModifier() + "(" + name + ")");
+        }
+    }
+}
diff --git a/source/net/yacy/search/query/SearchEvent.java b/source/net/yacy/search/query/SearchEvent.java
index bac4d5794..260ddc790 100644
--- a/source/net/yacy/search/query/SearchEvent.java
+++ b/source/net/yacy/search/query/SearchEvent.java
@@ -68,6 +68,7 @@ import net.yacy.cora.sorting.WeakPriorityBlockingQueue.ReverseElement;
 import net.yacy.cora.storage.HandleSet;
 import net.yacy.cora.util.ConcurrentLog;
 import net.yacy.cora.util.SpaceExceededException;
+import net.yacy.crawler.CrawlSwitchboard;
 import net.yacy.crawler.retrieval.Response;
 import net.yacy.data.WorkTables;
 import net.yacy.document.LargeNumberCache;
@@ -97,6 +98,9 @@ import net.yacy.search.EventTracker;
 import net.yacy.search.Switchboard;
 import net.yacy.search.SwitchboardConstants;
 import net.yacy.search.index.Segment;
+import net.yacy.search.navigator.Navigator;
+import net.yacy.search.navigator.RestrictedStringNavigator;
+import net.yacy.search.navigator.StringNavigator;
 import net.yacy.search.ranking.ReferenceOrder;
 import net.yacy.search.schema.CollectionConfiguration;
 import net.yacy.search.schema.CollectionSchema;
@@ -144,8 +148,6 @@ public final class SearchEvent {
     private final AtomicInteger expectedRemoteReferences, maxExpectedRemoteReferences; // counter for referenced that had been sorted out for other reasons
     public final ScoreMap<String> locationNavigator; // a counter for the appearance of location coordinates
     public final ScoreMap<String> hostNavigator; // a counter for the appearance of host names
-    public final ScoreMap<String> authorNavigator; // a counter for the appearances of authors
-    public final ScoreMap<String> collectionNavigator; // a counter for the appearances of collections
     public final ScoreMap<String> namespaceNavigator; // a counter for name spaces
     public final ScoreMap<String> protocolNavigator; // a counter for protocol types
     public final ScoreMap<String> filetypeNavigator; // a counter for file types
@@ -153,6 +155,8 @@ public final class SearchEvent {
     public final ScoreMap<String> languageNavigator; // a counter for appearance of languages
     public final Map<String, ScoreMap<String>> vocabularyNavigator; // counters for Vocabularies; key is metatag.getVocabularyName()
     private final int topicNavigatorCount; // if 0 no topicNavigator, holds expected number of terms for the topicNavigator
+    // map of search custom/configured search navigators in addition to above standard navigators (which use special handling or display forms)
+    public final Map<String, StringNavigator> navigatorPlugins; // map of active search navigators key=internal navigator name
     private final LoaderDispatcher                        loader;
     private final HandleSet                               snippetFetchWordHashes; // a set of word hashes that are used to match with the snippets
     private final boolean                                 deleteIfSnippetFail;
@@ -257,8 +261,6 @@ public final class SearchEvent {
         // prepare configured search navigation
         final String navcfg = Switchboard.getSwitchboard().getConfig("search.navigation", "");
         this.locationNavigator = navcfg.contains("location") ? new ConcurrentScoreMap<String>() : null;
-        this.authorNavigator = navcfg.contains("authors") ? new ConcurrentScoreMap<String>() : null;
-        this.collectionNavigator = navcfg.contains("collections") ? new ConcurrentScoreMap<String>() : null;
         this.namespaceNavigator = navcfg.contains("namespace") ? new ConcurrentScoreMap<String>() : null;
         this.hostNavigator = navcfg.contains("hosts") ? new ConcurrentScoreMap<String>() : null;
         this.protocolNavigator = navcfg.contains("protocol") ? new ConcurrentScoreMap<String>() : null;
@@ -267,6 +269,31 @@ public final class SearchEvent {
         this.topicNavigatorCount = navcfg.contains("topics") ? MAX_TOPWORDS : 0;
         this.languageNavigator = navcfg.contains("language") ? new ConcurrentScoreMap<String>() : null;
         this.vocabularyNavigator = new TreeMap<String, ScoreMap<String>>();
+        // prepare configured search navigation (plugins)
+        this.navigatorPlugins = new LinkedHashMap<String, StringNavigator>();
+        String[] navnames = navcfg.split(",");
+        for (String navname : navnames) {
+            if (navname.contains("authors")) {
+                this.navigatorPlugins.put("authors", new StringNavigator("Authors", CollectionSchema.author_sxt));
+            }
+            if (navname.contains("collections")) {
+                RestrictedStringNavigator tmpnav = new RestrictedStringNavigator("Collection", CollectionSchema.collection_sxt);
+                // exclude default internal collection names
+                tmpnav.addForbidden("dht");
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_AUTOCRAWL_DEEP);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_AUTOCRAWL_SHALLOW);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_PROXY);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_REMOTE);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_SNIPPET_LOCAL_TEXT);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_SNIPPET_GLOBAL_TEXT);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_GREEDY_LEARNING_TEXT);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_SNIPPET_LOCAL_MEDIA);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_SNIPPET_GLOBAL_MEDIA);
+                tmpnav.addForbidden("robot_" + CrawlSwitchboard.CRAWL_PROFILE_SURROGATE);
+                this.navigatorPlugins.put("collections", tmpnav);
+            }
+        }
+
         this.snippets = new ConcurrentHashMap<String, LinkedHashSet<String>>(); 
         this.secondarySearchSuperviser = (this.query.getQueryGoal().getIncludeHashes().size() > 1) ? new SecondarySearchSuperviser(this) : null; // generate abstracts only for combined searches
         if (this.secondarySearchSuperviser != null) this.secondarySearchSuperviser.start();
@@ -813,6 +840,19 @@ public final class SearchEvent {
         timer = System.currentTimeMillis();
 
         // collect navigation information
+
+        // iterate over active navigator plugins to let them update the counters
+        for (String s : this.navigatorPlugins.keySet()) {
+            Navigator navi = this.navigatorPlugins.get(s);
+            if (navi != null) {
+                if (facets == null || facets.isEmpty()) { // just in case we got no solr facet
+                    navi.incDocList(nodeList);
+                } else {
+                    navi.incFacet(facets);
+                }
+            }
+        }
+
         ReversibleScoreMap<String> fcts;
         if (this.locationNavigator != null) {
             fcts = facets.get(CollectionSchema.coordinate_p_0_coordinate.getSolrFieldName());
@@ -834,7 +874,6 @@ public final class SearchEvent {
                     if (host.startsWith("www.")) host = host.substring(4);
                     this.hostNavigator.inc(host, hc);
                 }
-                //this.hostNavigator.inc(fcts);
             }
         }
 
@@ -879,16 +918,6 @@ public final class SearchEvent {
             }
         }
 
-        if (this.authorNavigator != null) {
-            fcts = facets.get(CollectionSchema.author_sxt.getSolrFieldName());
-            if (fcts != null) this.authorNavigator.inc(fcts);
-        }
-
-        if (this.collectionNavigator != null) {
-            fcts = facets.get(CollectionSchema.collection_sxt.getSolrFieldName());
-            if (fcts != null) this.collectionNavigator.inc(fcts);
-        }
-
         if (this.protocolNavigator != null) {
             fcts = facets.get(CollectionSchema.url_protocol_s.getSolrFieldName());
             if (fcts != null) {
@@ -1303,6 +1332,15 @@ public final class SearchEvent {
             }
             
             // from here: collect navigation information
+            // TODO: it may be a little bit late here, to update navigator counters
+
+            // iterate over active navigator plugins (the rwi metadata may contain the field the plugin counts)
+            for (String s : this.navigatorPlugins.keySet()) {
+                Navigator navi = this.navigatorPlugins.get(s);
+                if (navi != null) {
+                    navi.incDoc(page);
+                }
+            }
 
             // namespace navigation
             if (this.namespaceNavigator != null) {