Similar to Donkey Punch wherein doing either doggie style or missionary, the male chuggs his beer then tries to pancake the beer can on the females forehead right before ejaculation. This makes it a lil bit tighter and gives you just enough time to run like hell for the door. This is a good tip for all you tree huggers worried about recycling.
Dude bro! I was with Jessica last night and everything was going fine till she called me dumb AGAIN. So I can-caked her right in the forehead before I came and havent called her since!