Here are some funny things to do to your friends who have foolishly passed out drunk on your couch:

• shave one of their legs and then draw on hair with a sharpey
• take random pictures using their own cell phone
• the classic hand in a bowl of water trick to make them pee themselves - warning - if you own the couch, you'll have to remove the urine smell yourself
• duct tape, almost anything involving duct tape
• put one passed out friend on top of another one in a comprimising position
• shaving cream, be sure to get really creative!
• build some kind of structure on top of them, this one is popular with engineering students
• putting a large clump of vaseline in their hair
• paper mache a hat on their head, or one of their legs
• if it's a girl, put a pregnancy test in her pocket with the test-positive indicator drawn onto it, this is even funnier if you plant one on a guy

Here are some things that are just NOT COOL to do to somebody when they're passed out:

• anything that could restrict thier airways or cause any kind of physical harm to them whatsoever
• shave off an eyebrow
• put any kind of permanent marker on their face
• anything that can cause a permanent scar
• anything that destoys their personal belongings

Now, these things are really funny to do, but we must stress that it's not alright to do anything to cause harm to somebody, and remember they will probably get back at you if you ever pass out.