Remove the shower head and place a chicken bouillon cube in it, then put the head back on.

 640

1  

Hide all of the desktop icons on someone's computer and replace the monitor's wallpaper with a screen-shot of their desktop.

 804

0  

Hide an alarm clock in someone's bedroom and set it for 3:00 a.m.

 743

0  

Fill someone's hair-dryer with baby powder.

 690

1  

Put a "Please Use Other Door" sign on the entrance to your office building if it only has one entrance.

 1372

1