Here's a prank that was played on a man who spent all day long assembling a 1200-piece LEGO Millennium Falcon set. After he went home for the day his friends took the thing apart piece by piece, put the pieces into their respective numbered bags and put them back in the box. This is a cruel prank, and the guy they played it on didn't know whether to laugh or get pissed off. I'm sure it was a little bit of both. On the bright side, he gets to have the fun or reassembling it all over again!