it just dawned on me, I can just give you the link to my php file and you can just upload a copy to your directory containing the sigs. If you go with x10hosting make sure you upload them to the images folder. It won't work in a folder that's not public.
Go to
http://blacksun.exofire.net/images/ and download the php file in the directory. (Right click and save link as)
Download that php file, and upload it into the images folder on x10 along with all your sigs. Then in the sig box here on stratics put {img]http://yoursitesURL/images/rotate.php[/img}
(obviously change the { and } to [ and ] )
You can customize the URL so it might not be the same as mine. It took me a few minutes to figure out the management page for the host, I recommend taking the tutorial they offer. Save yourself some grief.
If you decide to use another host, make sure they allow you to run php scripts. My ISP gives me free webspace, but won't allow it to run php so I had to find a free host (hence my using x10hosting). Hope this will help.