For all the pranksters out there....what was the funniest prank you've ever pulled?

A long, long time ago, when my kids were very young, we went on our annual camping vacation. I sent the kids out into the woods to look for a tree that was hit with lightning. I told them to look for shattered bark, a big crack, etc. They thought that they had found one. We walked back to that tree and I jammed the plug of this new invention, a rechargeable electric razor, into the bark. Lo and behold, the razor turned on. The eyes of the kids were as big as saucers and their chins hit the ground. They really thought that the tree had some left over electric from getting hit by lightning.

When I worked at a conference center that provided "room and board" ... The female dorm forked our (male dorm) lawn, as part of a "prank war" between the dorms.

Now, you need to know that both dorms had laundry rooms accessible to everybody at the center.  Ours in a shed, and theirs in the basement - where their hot water heater and breaker panel was located.

So, my prank was to shut off their hot water heater at the breaker.  They wrote it on the maintenance list - and I turned it back on, before the maintenance crew could "fix" it.  So maintenance crew saw nothing wrong.  Then, after maintenance looked at it, I shut it off again.  (and told maintenance this time, so they went along with it) 

Imagine a dorm of seven females, age 18-21, with no hot water for a week.  LOL - They were REALLY pissed when one of the other guys in my dorm leaked what happened.

I worked on a team of pranksters with a boss who was, luckily, a non-repentant jokester. We had pranks going on all the time. We got a refrigerator box, made a door for his cubicle, filled it to the brim with balloons. He opened the door and they just kept pouring out. We had a video going, filming this - five minutes later, the balloons had all spilled out into the aisle.

For his birthday, we made a huge spider web for his doorway (we had a thing about a cubicle doorway). Other people found out about this spider web and kept coming over to stick things to this spider web. It was too freaky because we made it HUGE to fit the "cubicle doorway".

For another coworker, we used black electrical tape and taped down the button on her phone, ran into the president's office and called her - she couldn't answer because we had taped down the button. We used black construction paper behind her privacy screen on her PC. She kept trying to "turn on" her PC, not realizing that it was on, because the black construction paper blocked her view.

Another time, we took dozens and dozens of red Solo cups and made a path from the elevator to my boss' cubicle all to celebrate his 50th birthday.

You name the prank I pulled it from saran wrapping my sisters car. To putting a snake in my others sisters car. Stuffing the exhaust on one friends car full of potatoes.