Find a sleeping person, fill their hand with shaving cream and then tickle their nose.
April doesn't fool Chuck Norris, Chuck Norris fools April.
Place a pair of pants and shoes inside the only toilet stall in a rest room to make it appear someone is using it all day.
Put tape over the optical sensor of someone's mouse.
Fill someone's hair-dryer with baby powder.
Hide all of the desktop icons on someone's computer and replace the monitor's wallpaper with a screen-shot of their desktop.
Put a "Please Use Other Door" sign on the entrance to your office building if it only has one entrance.
Remove the shower head and place a chicken bouillon cube in it, then put the head back on.
Install the Blue Screen of Death screen-saver on someone's computer.
Paint a bar of soap completely with clear nail polish so it won't suds up.
I just recently discovered that there is a national holiday named after Atheism. April FOOLS day. Like this story in the name of Jesus.