Anyone else here on DC using this spam filter? I've been testing it for quite a while now and I must say I'm very happy with it indeed:http://www.spamihilator.com/
It sits between your POP and IMAP accounts much like MailWasher - but it seems to have one step better integration, in that when I send/receive from my email client, it springs into action, then my mail arrives. So unlike MW, I don't need to keep switching between applications (well I do, but only once a day to make sure nothing got trapped that should not)
By now where I have it at the point where it's really well-trained and also has some nice custom filters: I'm basically spam free yet confident that everyone who should get through, does get through.
The filters are extremely versatile, and there is a plugin SDK available which means it's adaptable for some fairly specialised scenarios.
I'm nothing to do with these folks (except a donor to the project) but I think they could use some recognition.