CareerBuilder.com has issued a press release listing what they have determined to be the top ten office pranks, based on a survey of 2500 office workers. Here they are:

1. Change the caller ID on a co-worker's phone to read Mr. Kitten every time he calls someone.
2. Place random objects from people's desks in the vending machine.
3. Place a live goldfish in an IV bag in a clinic.
4. Sneak onto someone else's computer and send out an "I love you" email to the entire office.
5. Wall-paper someone's entire cube with headshots of his co-workers.
6. Pull the shelves out of the break room refrigerator, hide inside and jump out at co-workers as they open the door.
7. Sit on the copier and place the copies back in the paper bin. Anytime co-workers make copies, they have the image of the prankster's backside in the background.
8. Turn all the clocks in the office one hour back to make the work day seem longer.
9. Lock all the doors, shut off the lights and put a "Closed" sign in the window when the boss went out for lunch.
10. Place fake rubber chocolates in the break room and watch as co- workers try to chew them.

Which reminds me of another office April Fools prank someone told me about. (They swore they participated in it.) On April 1st everyone in the office quit, filing into the HR person's office one after another. Almost caused the boss to have a heart attack. Of course, the danger with that prank is that you might not get rehired.