You never known who you're going to be connected with at Chatroulette. Even... yourself? Kate trained a webcam back at the screen when she joined Chatroulette. Then she captured the looks on many people's faces when they "connected" with themselves. Link (embedded YouTube video)
And I think your cat roulette is missing an h =D
How exactly do you ruin a life with Chatroulette? Sure, it's not pleasant to see pictures of horrible internet memes, but then again you ARE attending a website that invites all sorts of jerks to do whatever they want. What did you expect?
Also, please note that 4chan != /b/. 4chan is quite a large place. I doubt the cooking or origami boards are much involved in this.
Cat Roulette
http://catroulette.tumblr.com/
Well, it involves misdeeds on both parties but you use a program to fake a webcam, say with a pretty girl or hot guy, you talk with the guy or girl, get an email address for future communication, have the fake webcam guy or girl get naked, then ask the "victim" to show you some goodies. If they do, you can track the email address they gave you to a facebook account. Usually they have set who their girlfriend or boyfriend is, then you forward them a screenshot of them showing on the webcam.
Often people will then post the email exchange of the victim begging the webcam faker to stop. I've also seen older dudes getting in trouble for exposing to "fake minors" but I don't really have a problem with this. Suffice to say, don't get naked and give personal information on chatroulette.
Oh and I did say, the "a-holes on 4chan" and we should all know where the "a-holes on 4chan" come from. I'm a stringent rule follower.