For some reason (presumably because I'm tall or because I have too much body fat (thanks Taco Bell!)), I have an extremely high tolerance to alcohol, despite the fact that I almost never drink. It can take upwards of 600ml of whisky for me to really "feel unsafe to drive" [1], which is part of the reason I don't really drink to begin with...If I don't have much fun with it, and it's not healthy for me, I don't really see the point in partaking.

[1] Don't worry, I've never tested this theory, I don't even own a car.