Warning: There is a NSFW picture on all these links.

rfjason decides it would be amusing to lure a bunch of guys into BDSM into giving him their personal information with a Craigslist personal ad, which he dubbed "The Craigslist Experiment".

He then posts their responses, as well as locations, e-mails and photographs, and invites people to look for people they know.

The comments house staggering numbers of people who find this amusing, and show that rfjason has a whole lot of time on his hands.

One of the identified showed up with threats of legal action.

"Actually, removing any of the information would have made the experiment null and void. I have principles to uphold, you know."

BDSM=abuse and torture, and you so deserve to have your life ruined if you enjoy it.

A mouse shows up to give the identified an opportunity for revenge!

Doms are no different than serial killers.

"We didn't do it to hurt anyone. We did it for the lulz."

ETA:
An article on Waxy.org explains the origin (apparently he is emulating an actual experiment), as well as the legal issues and gives some choice comments.

ETA 2:
There's also an entry on Wired about it, calling him a sociopath, and there's a fair amount of wank in the comments.

Apparently it's also been mentioned in metaquotes but I couldn't find it, and I waded through a whole lot of unfunny posts looking, believe me.