Idea for spam control

I just had an idea on how to handle most of the spam bots. Since %99.9 of the bots always post in the first forum they see why not create a "spam trap" forum and have it be the first forum listed. The spam trap forum would be for spam bots only. Anything that gets posted in that forum would instantly get deleted by a script or some kind of permission. Or Have it so the message must be approved before everyone can see it. Mods could ignore these messages or just delete them. I don't know if any of this is possible with vBulletin or if there are any add on scripts that can do this but I thought this would be a good idea to automate the spam removal.