The best prank I have ever successfully pulled off has got to be when I was in 8th grade a couple friends and I were skating at our school and my one friend went to the store, so while he was gone I took his skateboard and put it ontop of this ledge that you have to climb on the roof of the school to get to, but when you get up there, you can't see the ledge, so you have to guess where it is. My one friend spent six hours trying to find his skateboard DURING SCHOOL HOURS. The janitors were even helping him and none of the teachers cared XD