Everyone: with a crowd this big, it's only natural that once in a while someone nutty blows in.
If you see someone acting out or vandalizing, please don't reply. Your attention keeps them hanging around, and your reply is just more stuff we'll need to clean up. The best way you can help is by emailing us URLs of problem posts (to email@example.com - bookmark that address!) and then sit tight till one of us can get to it.