A good way to get back one of your friends. When you approach someone who is sleeping, you pull out your cock and balls, place your balls over their eyes and your cock down their nose thus creating the illusion of a centurion's helmet. Photos optional.
As other people have said 100 shots (beer) and 100 minutes. You may need a sober person timing if you are soft. If you have balls, go the double, this will get you fucked off your face and you will DEFINATELY need a timer.
If you cant make 100, everyone knows you are a pussy.