Yes, yes, and yes! four-chan is the worst! I'm part of 2 different sites that are sworn enemies of IIIIchan (Points to sig), and yet we still get trolls from 4C. there all the time. PC is lucky it doesn't have to put up with DDoS attacks, and other chantardism, because it is not fun at all.
And I'm sure Y! answers has a lot of trolls, but I'm pretty sure most of the people on there are just straight up stupid.