Vipul's Razor -- A collaborative spam filtering network.
Collabarative spam filtering tool. I think I'm going to set this up on unmaker, and start forwarding my mail through unmaker....
After further review, it would seem that this is /totally/ not ready for primetime. There is no way to hold someone accountable for their "This is spam" submissions. So, an evil person could cause you to not get all your mailing list mailings, etc. Too bad.