If talking about the opposite sex: Sluts. Sorry to put it so bluntly, but I can't stand girls that dress like a porsititute, and who's current political events only include 'Like that party at that guys house. Oh my god, you got so drunk!' 'Like shutup!'
I had to listen to something like this on the train all yesterday behind me going to Brissy. Arrgghh! I wanted to hit one of them.
And yes, one of them did say, 'Like shutup!'