I leave some space in front (not a car length) in case the idiot in front can't decide what they want to do.
People who dangerously weave in and out of lmtraffic only to wait for you at the next traffic light.
People who drive onto the road from side street at snail pace oblivious to anyone around them.
People who drag at the lights to get in front of you then do the speed limit or below. Get out of my way and stay out of my way. This is worthy of road rage, if I'm in the mood.
People who have no idea what they're doing behind the steering wheel and should clearly be doing something other than driving a car.
It's a privilege to drive a car, not a right.