Stewart is seriously cool...
I saw him once at a convention, and twice up near where I live when he did benefit one-man performances of "A Christmas Carol" in a small theater. During one of these performances, some fool threw him off stride with a flash photo, and got a first-class Stewart ream-out from the stage. Afterwards, I believe I saw at least two other people eat their own cameras.
He's done forewords for my favorite comic collections, voices for the most bizarre animated stuff, and a lot of other things to show that somewhere inside that flawless exterior beats the heart of a true geek.