As I have previously stated, I travel a lot, and always have. I am exposed to many more people in a month than most. I have had to brandish a firearm three times other than the one time I had to actually fire on someone.
Remember, I'm not talking about being out looking for a fight. I'm talking about nearly thirty years of putting in excess of one hundred thousand miles a year on my car. (Fortunately that has tapered off to something approaching reasonable in the last five years; about forty to fifty thousand miles a year.) I've seen more of the inside of my car or truck over the years than I have of the inside of my house.
The three times that come readily to mind all happened over five years ago. One was a case of mistaken identity. No $@#! there we were... I was in Colorado and a guy chased me into a parking lot and got out of his car with an ax. I pulled my Vaquero and he stopped dead in his tracks. He kept his distance and accused me of sleeping with his wife. I'd never met his wife and had been out of town for military training (I was stationed at Ft. Carson). I had just driven back into Colorado Springs from Maryland. I'd been on the road for three days, and I had been at Aberdene Proving Grounds going to school and working on the Xm1 project (yep the Abrams tank while it was still an experimental model) for the previous four months. The guy was a bit ashamed of himself and actually said that it was probably good that I was carrying because it was only the possibility of getting shot that originally kept him from opening my skull like a melon.
Now I have no idea how many potential fights might have been avoided in Colorado since I was carrying openly, but that was about the only thing that really stands out other than the fire fight I ended up in Denver when I was a courier, but that one doesn't count in this case because the BG's opened fire before I had a chance to even draw. What saved my life in that instance was quick reflexes and perps who were lousy shots.
The next instance happened after I was out (about seven years later) in Florida. I don't know exactly what happened, but I was driving my 81 Monte Carlo and some guy tried to run me off the road with a Plymouth Horizon. My car was bigger and I just hit the gas and moved on. The problem came when he caught up with me at a traffic light. I was boxed in and he ran up and yanked my door open, and he had a huge bowie knife in his hand. I stuck my Taurus model 85 right into his crotch and cocked the hammer back. He decided that whatever had made him angry wasn't worth losing the family jewels over and backed off. Like I said I have no idea what happened, we didn't exchange many words. The traffic was heavy and it's possible I could have accidentally cut him off while changing lanes if he was in my blind spot, but he never said, and the light turned green and I was able to drive away and leave him standing there holding his gonads in a protective manner.
The last instance happened about three years or so after that. A pickup truck with two young men in it tried to make a right hand turn from the left hand lane and we both had to do some fancy driving to avoid an accident. The driver of the truck got road rage and decided the whole thing was my fault. They followed me until I turned into a gas station (two blocks from the local police station) they drove up the road a bit then turned around and came back. They jumped out of their truck with baseball bats. I reached in the center console and grabbed my trusty Taurus. They got back into their truck and drove like maniacs to the cop shop. I drove to the same destination (after paying for my gas) and presented myself to the officer the two young men were frantically talking to. The police officer (someone I knew from running EMS in the area, and helping to train K-9s) explained to the two goofballs that baseball bats are just as deadly as guns and I had a right to defend myself. Interestingly, he even told made them stay with him while I drove away so that they wouldn't be able to follow me. (Sometimes the cops can be quite reasonable in such a situation, but it probably helped that he knew me.)
Mostly though, if confronted with a road rage situation my first inclination is to apologize: even an apologetic gesture can defuse the situation most of the time. It's taken me a while to learn that lesson, but even if it is the other guys fault, apologize. You'd be amazed how quickly you can disarm the situation without the threat of any kind of force providing you don't wait until things get physical. If that doesn't seem to be working and I am still in my car I simply head for the nearest police station. I don't think I would pull a gun now unless the other guy managed to run me off the road, or he opens fire (or at least brandishes a gun).
As for other situations, I just don't get involved in scrapes much. Although I was in a convenience store when it was robbed one time. I just stood passively until the guy started yelling for everyone to give up their wallets. He had a knife and I was standing next to the canned goods. I'm no Satchel Page, but I can wing a can of tomato soup pretty hard when it's necessary,and those things hurt when they hit you in the chest.