The nasiest prank I pulled was sending a certified letter to a couple of former friends of mind notifying them of a pending lawsuit from a former friend of theirs who wanted to sue them for slander & agrivation. Once when they got that, they flipped! They found out later when they arrived at the courthouse that there was no lawsuit filed against them on the docket & when they found out they got pranked real bad, they were madder than Hell that day. They were never told who sent them that letter & that's a good thing because they will never find out who did because I finally got the last laugh on them after all the crap they were pulling on me behind my back.