Ok, my top three (not in any sort of order):

1) Matt Damon - He seems pretty down to earth. Love that his Oscar is for writing, not acting.
2) Dick Wolf - I could tell him the plot to all of his shows ever. He'd probably tire of me pretty quickly.
3) Hugh Laurie - He seems like a blast. I'd ask him to speak only with an American accent though, which he probably wouldn't like.

What celebrity would you get along with best? I.e., who is your hypothetical celebrity bff?