This is why, along with training for my firearm, I intend to get training for my body as well.
I've been looking at alot of different martial arts. Krav Maga seems very interesting. I have several friends from Israel who all took this form of martial arts with their mandatory military serving time. Its very much based on being in a screwed up situation already, and a re-actionary styled defense. Such as being held at gunpoint, knifepoint, or someone coming to choke you, reacting and taking them out as quick as possible.
It also has firearms training built into it(at some schools).
If someone seemed really pissed at me for "cutting" them off I would of pulled into the gas station, and waited at the pump until I was sure they didn't follow me. I dont ever let my tank get to empty enough that I wouldnt of been able to just pull away.