It might not be much use but
i developed this script it is very short and may be useful to may of you.
<script language="javascript">
function pp(x){
var f
f = 'pic.asp?ID=';
f += x"f", "boo", "toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,resizeable=0,width=800,height=600");
// done hiding -->
for an image to use it use
<a href="#" onClick="pp('a')"><img border="0" src="peeps.gif" width="42" height="43"></a>
and for a hyperlink
<a href="#" onClick="pp('a')">MY LINK </a>
tihs code is usefull in the fact that if your pages are dynamic or severside generated you can access which link was clicked and show relevant stuff.

an example of this maybe a photo gallery written from a database, all links are written dynamically and the pic id could be passed to the popup and the page in the popup can write the relevant pic/information from the database.