they should know better than to surf with AOL, just like you wouldent design websites for a resolution of 640x480 just because some idiots are fixed on using it :)

A few years ago when using WWWBoard I had a major problem with abuse from open proxies. My solution was to modify the WWWBoard script to scan the poster's IP address for common proxy ports that were open. This did restrict a small amount of legitimate users from posting, but it stopped the abuse dead in its tracks. Back then I didn't consider the implications, but if a solution like this was tried today, I'd recommend making the user click through a disclaimer message that tells them that their IP address will be scanned, and the reasons why. Trying to maintaining a list of known proxies isn't the way to tackle this problem. They'll always be one step ahead of you.