You guys need to quit drinking prune juice

A friend of mine in college did something similar as a prank. He came home from school early for a week and cleaned out his roommate's cat's litter box and basically made it look like the cat hadn't used it.
Then, the day after the roommate approached my friend because he was concerned that his cat hadn't crapped for so long, my buddy comes home from class and drops a huge log in the litter box. Several of us were there playing video games when the roommate came home and got to see his reaction.
Priceless.

This...is...just...AWESOME
