I was in the car with my dad once and a guy behind us beeped because the guy in front of us was taking forever to turn at a stop sign. Guy in front gets out being semi tough and asks what's up. My dads immediate response was to yell "I'll blow your fucking head off if you take one more step". It was like 0-100 in less than a second. Luckily the guy went pale and got back in his car because that was in no way an empty threat. The person behind us opted out of beeping for the rest of his life.
Road rage is fucking stupid though. At some point I just stopped caring and laugh whenever someone gets all mad at me (which is rare). If the situation called for it I would just run someone down instead of fighting. It's like I can probably kick your ass, but I know for a fact you can't beat up my car.
Once i was at a stop light and i completely spaced out and let off the brake right into the car in front of me, a huge fat hells angel looking guy got out of the car and looked at me and just shrugged and got back in his car and left.