I almost crashed the car today when doing about 45-50mph on a 40mph road, and didn't notice the traffic light ahead was red - had to do an emergency stop and ended up stopping right in the middle of the crossing. Fortunately there were no cars behind me and no-one was crossing the road at the moment, but yeah, I was an idiot for not noticing it, especially as it's a road I use regularly and has traffic lights all the way up and down. Other car incidents haven't been my fault, mainly when I've been cycling, sticking to the designated cycle lane, and taxis have come at high speed (despite the heavy traffic) roaring into the cycle lane not caring that I'm there trying to stay alive. Leeds has some of the stupidest taxi drivers I've ever seen...
I also almost drowned when I was a kid, when I was in Wales, kayaking on Bala Lake. I capsized, rolled right under the water, and couldn't remember how to get out of the kayak the way the instructor had showed me. I managed to get out eventually (clearly, or else I wouldn't be telling this story), but that was a scary moment...