scrolling DHTML auto popup window for specific usergroups

[yoyoyoyo]

how can I add a scrolling DHTML popup window (that follow you around as you scroll around) for usergroups that I specify? I have seen popup boxes on sites for non-registered users, so I assume it is possible with any usergroup, but I don't know how to add that option, and would appreciate knowing how.

[WetWired]

If you give a box the css "position:fixed;", you can position it relative to the browser window instead of relative to the page. This isn't DHTML, though, it's part of the CSS standard.

[yoyoyoyo]

cool- thanks. How do I make it conditional?