I think you guys have hit just about all of them, but I can still add a couple...
Billy Crystal - I saw a clip of him be a real Ahole to a little boy that wanted his autograph. He didn't know he was being taped and was a real jerk. Poor kid.
And he reminds me of Whoopi Goldberg. I don't know why but she just annoys me.
But the all time loser to me is Tom Cruise!