I've never timed it, but I do try to do realtime-spam detection on blog/forum comments: http://blogspam.net/ http://blogspam.net/ Although it operates at a mu

I've never timed it, but I do try to do realtime-spam detection on blog/forum comments: http://blogspam.net/ http://blogspam.net/ Although it operates at a much smaller scale than most of the things linked to here it does work pretty well.