I know a javascript code which will prompt the user to bookmark your page:
You will need to change the following to your own details
var url="ENTER YOUR WEBSITE ADDRESS HERE";
var title="ENTER A TITLE FOR YOUR SITE HERE";
Here's the code:
<script language=javascript>
<!-- Begin
if ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4)) {
var url="ENTER YOUR WEBSITE ADDRESS HERE";
var title="ENTER A TITLE FOR YOUR SITE HERE";
document.write('<A HREF="javascript
:window.ext');
document.write('ernal.AddFavorite(url,title);" ');
document.write('onMouseOver=" window.status=');
document.write("'Add my site to your favorites!'; return true ");
document.write('"onMouseOut=" window.status=');
document.write("' '; return true ");
document.write('">Add my site to your favorites.</a>');
}
else {
var msg = "Don't forget to bookmark me!";
if(navigator.appName == "Netscape") msg += " (CTRL-D)";
document.write(msg);
}
// End -->
</script>
I also know that you can make something happen when the page is closed using:
<BODY onUnload="Here you need to put something which will activate the javascript code. I'm not sure what though">
I also know that if you save your javascript as a .js file using notepad (take out the <script language=javascript> and </script> if you do this though) you can use:
<SCRIPT SRC="Name of script.js"></SCRIPT>
That's all I know, hope someone else knows the rest.
Martin 
Unsolved 
