the loudmouths get louder and the silent suffer...until they snap and beat you to death with a tire iron.
Ain't that the truth?

My favourite time was sitting watching The Punisher (Tom Jane, 2004) for the second time. I had seen it once previously, and had shushed a group all through the fight with 'The Russian'. Anyway, the scene starts up, and all of a sudden behind me, a guy goes, "Oh my god - OH MY GOD THIS IS GREAT!" and I shush him. The scene continues, he starts gushing over how exciting it all is, and I shush him again. He slaps his hands together, and says something to the effect of "HOT DAMN!" and I lose it - I turn around and say, "Do you mind? Please be quiet!"
It's quiet for the rest of the movie. When I get up at the end, I feel a heavy tap on my shoulder - I'm standing, a row down from the guy. I'm 5'9" tall. He's sitting, and I can already see he's taller than I am. He stands up - easily 6'4" - and leans in towards me. He says, "Hey man, I'm really sorry about all that - I just got really into the movie, that's all."
I'm sure you can imagine my adrenaline rush by that point, and I was now happy that it was slowly lowering. (While I wasn't too concerned that it would have become heated, and even if it had as I've been in similar situations, but I'm certainly not looking to pick a fight where I'll be the obvious underdog.) I told him all about how I missed the scene the first time I had seen the flick, and he apologized again, and shook my hand on the way out.
Maybe it's the fact that he was surprised that a small guy like myself would dare call a big guy like him out, but I like to think that there are all sorts of people in the world who aren't automatically douchenozzles when confronted for doing something wrong.
