i suggest using the
www.addthis.com button to your pages..
this will allow users to bookmark your page or add it to their favourite bookmark site like "digg" "redditt" etc
or use this simple javascript but the above is better
Code:
<script>
function setBookmark(url,str){
if(str=='')str=url;
if (document.all)window.external.AddFavorite(url,str);
else alert('Press CTRL and D to add a bookmark to:\n"'+url+'".');
}
</script>
<a href=# onclick="setBookmark(parent.location.href , document.title );">bookmark this page</a>