I avoided a fight in a movie theater with a flashlight.. was EDC'ing a Nitecore EX10 at the time. The guy in front kept using his cellphone during the movie and I politely (seriously.. I was polite) asked the individual if he would stop. He stood up, turned around, and started threatening me so I whipped out the EX10 and blasted it in his face on full power. I don't think he knew what to do, so I think he tried to act tough by staring the light down. Seconds later, he turned around, sat, and had his hands over his eyes for the next few minutes.. shortly thereafter, his friend escorted him out of the theater.. I think he went to the bathroom to either rinse his eyes or throw up.
They came back minutes later, but it was obvious he wasn't watching the movie and he had his head in his hands at least half the time. He and his friends waited for me outside the theater after the movie. I acknowledged him with a nod while passing by and made my way into the crowd with my friends.. they didn't say anything or follow and that was the end of it.
Although in hindsight, what I did was probably both stupid and reckless, the point is that the light from a flashlight can be an effective deterrent. I'm sure there are a thousand opinions on this, but I would suggest you carry a flashlight with the mentality that it is a useful tool and not a combat tool. Although it can be used in many different ways, equally effectively, I don't allow whatever light I'm carrying to give me any unrealistic sense of security.. although it's probably the first thing I'd reach for if things got hairy. Seeing as you EDC a pistol, you probably already have a mature understanding of what I'm getting at.
-\Visdom