I saw this awhile back but chatting with Ashley reminded me of it. Friends prank a buddy, Thad into thinking he won the lottery: They recorded the previous night's lotto number and inserted a ticket with those numbers into a batch of lottery tickets Thad purchased. While he's checking his numbers, his buddies play back the previous night's recording while taping his priceless reaction.
[youtube=http://www.youtube.com/watch?v=ZovM93QZRKo&fmt=18]
They all eventually appeared on the Today Show:
[youtube=http://www.youtube.com/watch?v=vXzAbUo93WU&fmt=18]