Some physicists have worked out what Usain Bolt's time in the 100 meters in Beijing would have been if he hadn't started celebrating before the finish line: 9.55 seconds. The original paper is here. I tried doing this the day after the race but even the HD footage wasn't good enough to see the tick marks on the track and I didn't want to mess around with all the angles. (via justin blanton)
Update: The folks at The Science of Sport lay out a much more sensible case relying on split times that Bolt would have run somewhere between 9.61 and 9.69. (thx, jim)