Adds full screen toggling in the tool bar as suggested by @deleolajide .

app.js

@@ -1110,3 +1110,34 @@ function scrollChatToBottom() {
         $('#chatconversation').scrollTop($('#chatconversation')[0].scrollHeight);
     }, 5);
 }
+
+
+/*
+ * Toggles the application in and out of full screen mode 
+ * (a.k.a. presentation mode in Chrome).
+ */
+function toggleFullScreen() {    
+    var fsElement = document.documentElement;
+
+    if (!document.mozFullScreen && !document.webkitFullScreen){
+
+        //Enter Full Screen
+        if (fsElement.mozRequestFullScreen) {
+
+            fsElement.mozRequestFullScreen();
+
+        } 
+        else {
+            fsElement.webkitRequestFullScreen(Element.ALLOW_KEYBOARD_INPUT);
+        }
+
+    } else {
+
+        //Exit Full Screen
+        if (document.mozCancelFullScreen) {
+            document.mozCancelFullScreen();
+        } else {
+            document.webkitCancelFullScreen();
+        }
+    }
+}

index.html

@@ -7,7 +7,7 @@
     <script src="//code.jquery.com/ui/1.10.4/jquery-ui.js"></script>
     <script src="muc.js?v=4"></script><!-- simple MUC library -->
     <script src="estos_log.js?v=2"></script><!-- simple stanza logger -->
-    <script src="app.js?v=15"></script><!-- application logic -->
+    <script src="app.js?v=16"></script><!-- application logic -->
     <script src="smileys.js?v=1"></script><!-- smiley images -->
     <script src="replacement.js?v=5"></script><!-- link and smiley replacement -->
     <link href="//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css" rel="stylesheet">
@@ -35,6 +35,8 @@
             <a class="button" onclick='openChat();'><i id="chat" title="Open chat" class="fa fa-comments fa-lg"></i></a>
             <div class="header_button_separator"></div>
             <a class="button" onclick='openPreziDialog();'><i title="Share prezi" class="fa fa-desktop fa-lg"></i></a>
+            <div class="header_button_separator"></div>
+            <a class="button" onclick='toggleFullScreen();'><i title="Enter / Exit Full Screen" class="icon-fullscreen"></i></a>
             <!--span id="settingsButton">
                 <div class="header_button_separator"></div>
                 <a class="button" onclick='openSettingsDialog();'><i title="Settings" class="fa fa-cog fa-lg"></i></a>