Lucky laptop

I was at an educational conference by the computer firm RM a few years ago. There was an incentive to stay all day as there would be a raffle of a swanky new laptop at the end of the day for anyone who was left. For the final session I was sat in a room of about 400 people in the front row. The presenter came over to me at the end with a big box of tickets and asked me to draw one out. When he referred to his list he announced that the winner was me! What are the chances of that?
Total votes: 537
Date submitted:Fri, 13 Jan 2012 14:32:32 +0000Coincidence ID:3360