practical jokes are my specialty.
i've done everything from getting a flock of geese to attack a buddy in the front of my canoe (after he hassled them earlier) by spreading doritos across the water behind his back. the best part is he's terrified of birds and can't swim; to, in an escalating battle of practical jokes with a co-worker, i wrote my home phone number inside a matchbook from a strip club with the name bambi, and put it in the guys briefcase, knowing his jealous wife would search it as she did often. i got my neighbor to record her voice as bambi on my answering machine. you shoulda heard the message his wife left. it was fun listening at work the next day at work when he came in. sadly, they're divorced today...
there was another co-worker's kid who kept screwing up my computer downloading stuff when his dad brought him in and i wasn't around. i warned him many times to stop, but he just mocked me, in his 13 year old annoying way. so, one thanksgiving, i squirted habanero juice all over his dinner, and i enjoyed watching him sweat as his father made him eat it. the kid was known for being a picky eater, so i knew his dad would force him to eat some and wouldn't listen to the kid's complaints. it was worth paying for another meal from the cafeteria.
another co-worker left his lottery ticket on his desk, so we copied down the numbers. later, when he asked me to tell him the numbers out of the newspaper i was reading, i repeated his numbers. we let him think he won millions for a while, until he was about to leave. there were a few priceless moments that i thought he was going to go give our boss a piece of his mind. we all swear we wouldn't have let him do that, tho.
similarly, at a friend's younger brother's 21st birthday, we gave him one of those fake scratch off lottery tickets. he didn't know that he didn't win $50k until the next morning.
this all started when i was a kid. my dad would feign heart attacks very convincingly, getting my mom really upset. he even told me she passed away one april fool's day. my brother was the master of telling you to "go long, go long" when having a catch with a football, then he'd run in the house because he heard mom call us in for dessert and i hadn't because by then i was all the way down the street. or he'd keep looking over your shoulder, and when you'd look, there went the rest of your dessert.
sundays were the only day my sisters were allowed to eat breakfast in front of the tv, so we had to rotate turns on what shows we wanted to watch. if my next oldest sister really wanted to watch something, but it was my turn, she'd whack herself across her face, leaving a nasty red handmark, then pretend to cry and call my mom, saying i did it. my poor mother would then drag me into the kitchen by my ear with my sisters giggling, changing the channel.
when my brother went off to vietnam, my sister and i put barbies and g.i.joes in his duffel so when he got to the base and dumped it out on his bunk, the other soldiers would see them.
of course, the old classics of "the birthday cake kinda smells funny"---whap, and tying shoe laces together, and pretending to hack off a limb and squirt blood are being taught to the new generation at all family gatherings.