Harold Various is a terrific scientist. He was awarded the 1989 Nobel Prize in Physiology or Medicine for discovery of the cellular origin of retroviral oncogenes. From 1993-1999 he was director of the National Institutes of Health, and is currently President of Memorial Sloan-Kettering Cancer Center in New York.
On top of all those accomplishments, he is a great advocate for science, and knows how to use traditional media, like TV and radio, to publicize his positions. Last night he was on the Daily Show with Jon Stewart.