The Spilled Milk Prank

Take a piece of glass. Spill some white glue on it (Elmer's). Let the glue dry out for good 6 to 8 hours. Carefully separate the glue from the glass. Place the dried glue on your colleague's keyboard, laptop, printer or even desk, and watch their scared face! 

This Post Belongs To 15 Hilarious Office Pranks You Can Try On Your Coworkers