Lance Armstrong is the one of the greatest athletes alive. He's beaten cancer, can push his body to levels never thought possible, and continues to dominate the Tour De France.
He's basically won the whole thing, and he won it by killing everyone in the mountain stages, by just blowing everyone away in the steepest sections. But the thing that really amazed me was seeing him win the 13th stage and finally take the lead and the yellow jersey. It wasn't just his performance that day, it was his tremendous sportsmanship.
In a world of sculpted helmets and frame tubing, bladed spokes, and time trials, every second counts. When his main rival Jan Ullrich veered off the road next to him and crashed on a downhill turn, Lance didn't take advantage of it and charge onward. He let up, looked back and waited for Jan to return to the race. Later in the stage, he broke away from Jan and won by a minute, but during those few minutes he let up to wait for Jan to catch back up or hear if Jan was out, that's when he earned my respect.
(yeah, I know he used to be a real cocky bastard in the early 90's, during his pre-cancer days, but his transformation over the past few years has been amazing)