I just saw him give a talk at Thotcon in Chicago about catching one of the first hackers and it was by far the best talk I've seen in quite a while. He's eccentric, animated, and an amazing storyteller.
CliffStoll
Oh, Thotcon was way fun, Server of cobras. The organizers gave me liberty to fool around, and there was a full house. Terrific time there!
tptacek
I saw him give a talk in the late 1990s and he was one of the best presenters I've seen, I'd go out of my way to see him if you have a chance.