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

 887

0  

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

 795

0  

Fill someone's hair-dryer with baby powder.

 752

1  

Change the coffee in the office coffee maker to decaf.

 1439

1  

Put tape over the optical sensor of someone's mouse.

 858

1