See presentation by Luis von Ahn at http://video.google.com/videoplay?docid=-8246463980976635143
He talks about how spammers use porn sites to correctly input captchas back in July of 2006.
He talks about how spammers use porn sites to correctly input captchas back in July of 2006.
Folks that haven't watched this talk... you should. It really got me thinking in new ways. There's a reason why von Ahn won a MacArthur ("Genius") Grant for his Human Computation work.