I was looking through some old folders while organizing files on the new computer, and found BannerMonkey, a script I wrote and then forgot all about (if I in spite of memory have posted it before I apologize).
What it does is rotating banners and their relevant links in forum signatures, in spite of any code bans the forums may be enforcing. All you need to do is edit the script underneath to reflect your graphics and links, upload it to your server, and then insert a static HTML or UBB code in your signature. The script is able to redirect clickers to the right URL because the rotation is based on hour. At 1AM and 1PM for example, the script shows the graphic associated with that hour, and clicks that happen in this period are redirected to the associated URL.
The script:
http://www.enlarge.org/bannermonkey1.0.zip