I was in a pretty bad car accident in May 2009. I was driving to work down a mountain road in my little Mazda 3 and some jackass in a Navigator comes around a bend, going far too fast. He skids over the median and hits me head-on. I was going ~60mph, the cop I talked to a few weeks later said the other guy was going 80+. Those of you that have had the misfortune of being on head-on collisions know that you get about a quarter-second to react before you get hit. For me, it was basically enough time to think, "Oh, !@#$" and for my legs to lock up.
Anyway, he hits me and my car goes spinning off, eventually coming to rest in the middle of the road. My windows are all shattered, and I can't see through the windshield due to the spiderwebbing. My head is throbbing, and I can tell I'm bleeding from it. My arms have glass in them, and I can see in what's left of the rear-view mirror that I've bit almost completely through my bottom lip. The dash is about a foot closer than it had been a minute ago, and the airbags were deployed (airbag dust smells awful, just by the way). I move my right leg, and then try to move my left one, only to find that it's unresponsive. I look down and see the top half of my femur moving against my skin when I try to move my leg. Suddenly, it dawns on me that I'm in ridiculous pain.
So I'm sitting there grinding my teeth to keep myself from screaming, and I think, "huh, isn't there a huge !@#$ing artery next to your femur?" Then I decide to notice that my leg is swelling up. Great. So I sat there for a minute thinking that I was going to die, before realizing that if I were to bleed to death I probably would have done it by then. But sitting there for a minute thinking I was going to die wasn't particularly fun.