The one me and my friends usually play is, drink until you're out of beer, go buy more and then keep drinking that until it's gone
Never really done any drinking games as we've never seen the point. Measures for spirits on the other hand...
We usually do the old penny test for vodka, gin, sambuca etc...
Put a penny in a glass, fill it with coke until the penny disappears (you have to be right over the glass for this to work properly) then fill the glass with your choice of alcohol until the penny becomes visible again
