A small idea I had lately, thank-you goes to Anony.
Okay, why do the bots post in this board? I'm not sure how they select the board to post their spam. It's not by name, since the name change didn't change anything (or did it? Idiota or someone, did the numbers lower?). It's not by board number or position, since Intelligent Conversation is somewhere in the middle (the ones who post in Magebane are using this method). So what is it?
I think they pick the one with the highest postcount, which kind of makes sense (it's the one most people read). So, perhaps a strategy could be to create a new board, fill it (script-wise) with nonsense topics and posts so that its numbers far exceed Intelligent Conversation, and see how the bots will act. Perhaps they'll all swarm to the new board. We can then make a script (I am willing to) to destroy any idiot that posts in that board.
Not too sure what Ville would think about having such a mess in his forum, though.
[EDIT]Another idea. Why don't we apply the usual spam filters to this forum? There are pretty nice Bayesian filters for mail, and I don't think it's too hard to get/make one for a phpBB board. I don't see why it wouldn't work...