1. Make a fake post on Craigslist offering 54 free goats with your friends number
2. Put googly eyes on all the food in the fridge.
3. Order a pizza for your roommate before you get home. Ask him to get it from the door. Wait at the door for the pizza guy to come without him knowing. Convince him to let you put a pair of panties on top of the pizza. Let the delivery guy deliver the pizza to your friend.
4. Glue peoples shoes to the shoe matt.
5. Replace peoples laundry with a thanksgiving dinner before they switch the load.