Comment SPAM Wiper is a distributed solution for fighting comment SPAM (aka blog SPAM) that automatically filters the SPAM comments.
Comment SPAM Wiper checks your comments against the CSW web service to see if they are SPAM or HAM. If a SPAM comment is detected it is automatically moved to SPAM folder. If a SPAM comment is not detected and you manually mark it as SPAM, Comment SPAM Wiper will learn and in the future it will detect it as SPAM. CSW learns and improves detecting blog SPAM as it goes.
You will need an API Key (http://www.spamwipe.com/signup.html) to use it. The API Keys are FREE of charge.