bbPress.org

Unfortunately all Graham/Bayesian algorithms are doomed to fail, spammers have learned how to defeat even the best of them.

The best way to detect is counting the number of links in a post (in html or plain text) and holding any messages with more than 3. Of course they will adopt after many sites start doing that.

I am working on an advanced module for Human Test that will also check these databases, though some require membership:

fSpamlist

StopForumSpam

Sorbs

Spamhaus

SpamCop

ProjectHoneyPot

Bot Scout

DroneBL

It’s too “expensive” (in time and connections) however to check all of them on an active site for each post, so I’ll probably limit it to just registration, and maybe the first few posts a member makes.