Edit in JSFiddle

$("<a />", { 
    id : "show",
    text : window.location.pathname.indexOf("show/light") > 0 ? 
    "View Full Screen" : "Edit using jsFiddle", 
    href : window.location.pathname.indexOf("show/light") > 0 ?
        window.location.pathname.replace(/light\/$/gi, "") :
        window.location.pathname.replace(/show\/$/gi, ""),
    target : "_blank"
}).appendTo('body');  

<script type="text/javascript">
    firebug.env.height = 200;
    firebug.env.debug= false;   
    firebug.env.detectFirebug = true;  
</script>

#show {
    position: fixed; 
    top: 0px; 
    right: 0px; 
    padding: 5px;
    background-color: #3D6F9A; 
    color: #ffffff; 
    border-bottom: 1px solid rgb(153, 153, 153);    
    border-left-width: 1px solid rgb(153, 153, 153); 
    -webkit-border-bottom-left-radius: 10px;
    -moz-border-radius-bottomleft: 10px;
    border-bottom-left-radius: 10px;     
    border-right-width: 0px; 
    border-top-width: 0px; 
    text-decoration: none; 
    color:#FFFFFF;
    font-size:11px;
    font-weight:bold;
    text-decoration:none;
    text-shadow:0 1px 0 #0C131C;
    font-family:"Lucida Grande","Lucida Sans","Lucida Sans Unicode","Luxi Sans",Tahoma,sans-serif;
    display: block; 
}