To play this game all you'll need is some players, some drinks (preferably beer) and dig out a copy of Bill and Ted's Bogus Journey.
You can play this in teams, or not, but person or team has to choose whether they would like to be Bill or Ted. Tough choice. Pick your drink of choice and watch the movie.
When Bill says "Dude", the person who chose to be him has to take a shot or swig of drink, and then vice versa with Ted. As the movie rolls on you'll be surprised how often each player gets their turn.
Cant decide on what drinks to use? Try shots of rum and tequila.