I once happened upon an accident on the highway right as the first responders were getting there. The driver hadn't been wearing a seat belt and he went through the windshield and there were pieces of him splattered all over the road. It's odd how it doesn't really seem like a person when you first see it. Then after a second you realize how fucked up it is.
I wasn't there when it happened, but needless to say after that I wear my seat belt every time I'm in a car.