Even when he was little, Tyson Gay was fast ("I could steal a few bases," he says of his childhood baseball days), but he was 14 or so before he could beat his sister, Tiffany, who's a year older. "She had a quick start," he explains. "She inspired me."

Tiffany did a fine job, because her little brother went on to become a three-time Class 3A 100m state champ out of Lafayette High School, with his 10.46 state-meet record as a senior in 2001 still standing. Tyson followed that up by becoming the first athlete in University of Arkansas history to win an NCAA 100m title.

Now, he is also a triple World Champion. At the 2007 World Championships, Gay became only the second man in history to win titles at 100 meters, 200 meters and the 4x100-meter relay. He is also the new American Record-holder at 100m, thanks to a 9.77-second victory in the quarterfinals of the 2008 Olympic Trials. As an encore, Tyson clocked a phenomenal 9.68 in the final — wind-aided, but nonetheless the fastest 100 meters ever run by a human being.