re: a-hole celebrities and here are the rules:

Most of my encounters have been with athletes.
Roy Jones Jr: incredibly nice. Played a game of pick up basketball with him. Dude was soo quick
Bill Elliott / Kyle and Adam Petty / late Neil Bonnett - incredibly nice.
I shook Andre the Giants hand ( I will count that as being a cool dude since he took time out to do that)
Had a quick conversation with Bubba Watson ...he was very nice. Respective kids were on a play ground. It was just before a Bama UGa SECCG and he gave me grief over the Bama shirt but very nice


Don't know if it really counts a "meeting" but in Dublin Ireland Temple Bar area...I had read in the inflight magazine on the way over that celebrities hang out there a lot...well walking through there I saw Heath Ledger just sitting on the curb. I stopped and did a double take he looked up and laughed and I walked on. Either no one recognized him or didn't care but there was the joker just sitting on the side walk ( this was just before the release of the film )