I have posted a list of my banned users on my website.
They've all been banned for posting comment links to viagra/oxycodone/polo or anything else that has nothing to do with my site content. Its a small list because I operate a small site but I think if we all could post these lists and then aggregate them together we may be able to combat spamming more efficiently. If something like this has already been done, please point me to the module.
Here is my link:
IM SICK OF SPAMMERS!