better :q

content/commands.js

@@ -1350,8 +1350,9 @@ function Commands() //{{{
     addDefaultCommand(new Command(["q[uit]"],
         function() { vimperator.tabs.remove(getBrowser().mCurrentTab, 1, false, 1); },
         {
-            short_help: "Quit current tab or quit Vimperator if this was the last tab",
-            help: "When quitting Vimperator, the session is not stored."
+            short_help: "Quit current tab",
+            help: "If this is the last tab in the window, close the window. If this was the " +
+                  "last window, close Vimperator. When quitting Vimperator, the session is not stored."
         }
     ));
     addDefaultCommand(new Command(["quita[ll]", "qa[ll]"],

content/tabs.js

@@ -172,8 +172,12 @@ function Tabs() //{{{
             count = 1;
 
         if (quit_on_last_tab >= 1 && getBrowser().mTabs.length <= count)
-            vimperator.quit(quit_on_last_tab == 2);
-
+        {
+            if (vimperator.windows.length > 1)
+                window.close();
+            else
+                vimperator.quit(quit_on_last_tab == 2);
+        }
 
         var index = this.index(tab);
         if (focus_left_tab)

content/vimperator.js

@@ -812,8 +812,17 @@ const vimperator = (function() //{{{
             for (; now - then < ms; now = new Date().getTime()) { 
                 mainThread.processNextEvent(true); 
             } 
-        } 
+        },
 
+        get windows() 
+        {
+            var wm = Components.classes["@mozilla.org/appshell/window-mediator;1"].getService(Components.interfaces.nsIWindowMediator);
+            var wa = [];
+            var enumerator = wm.getEnumerator("navigator:browser");
+            while (enumerator.hasMoreElements())
+                wa.push(enumerator.getNext());
+            return wa;
+        }
     } //}}}
 })(); //}}}