In this posting, Dave writes about his idea for spam avoidance. Instead of making rules to copy the emails you don't want, copy the ones you do like.

This sounds remarkably like a manual implementation of the Receptionist Mail Origination Protocol (RMOP), something I wrote about earlier. I really think that the only way we will truly get rid of spam is with something like this. Maybe we need to build something like RMOP into SMTP. I get almost 100 spam messages a day and if it weren't for CloudMark SpamNet, I wouldn't be able to control it.