Prank jokes?

I have a co-worker who is constantly playing prank jokes on me...

telling the boss I was 'knocked up"...just for a laugh

putting plastic wrap in my coffee cup... taping important papers to the floor or on the wall just out of my reach....super gluing my pen to the desk top...

Now Im not innocent in this...Ive pranked him too on several occassions...but Ive run out of cool ideas..

please send me your best prank joke...nothing that will cause him to get hurt or fired...just something that would be frustrating and funny to watch

Prank jokes?-Myspace pictures

put small pools of water on his desk in the same spot when he's not looking. he'll keep calling the building maintenance people to check it out. With a bit of luck they will move his desk, stand on it etc.

Prank jokes?

-(Myspace images myspace.com)

Crush up a pencil lead and put it on the ear piece on his telephone.
鐪墊||take apart his phone,put crushed garlic and onion near the mouthpiece and tape it there.Re-assemble the phone and let it work its magic.