When some retard has got themselves stuck in the middle of the intersection, don't squeeze right up to them and box them in, give them space and let them get out. It's much faster for everyone. (not super rare, nice people do this)
When you park on a line of cars, and you are the last one that can fit on the available curb space, don't pull right up to the car in front of you. Instead, park as far back as you can on the curb, potentially leaving some space between you and the next car. This is significant because parked cars are not permanent fixtures. (I've never seen anyone but me do this). Quite a bit more people get this one right when they are parking on the front of the line, presumably because if you put something right in front of someone's face they tend to go for it.
People are so retarded.