I must admit:  I love pranks.  The scarier the better.  Especially when the prank is set up with hidden cameras for all the world to enjoy.

This one is for the necrophobics:

 

Want a free make-up session at the mall? Be careful!

 

Need help at the service desk? Try to keep a straight face!

 

Afraid of water monsters? Don't go after your wallet!

 

Not the funniest one, but still good for a start.

 

And finally, my favorite, the "Dropped Mannequin Head" prank.

 

(Via Youtube)