Someone else brought this up to pg himself but I'd much rather see the community answers to this very question.<p>Right now I'd have to say my favorites are:
Ray Kurzweil
Elong Musk
Michio Kaku<p>I'm sure there are plenty of wonderful ones that I overlooked, but these came to mind. (I'm probably just in a physics-kind-of-mood, plus I <3 inventors.)
James Burke.<p>I know he got a HUGE boost in popularity recently on Reddit and HN, but I grew up with archaic copies of his videos on VHS from the public library. Throughout the years, I've always been blown away by Connections' ability to explain the impact of science in an interesting and fun way.<p>I heartily feel that the general public would have a much greater interest in science if the history behind the science was taught in school in a manner similar to Burke's manner.