Hitchhiking home from high school (I know, I know) and get picked up by a really weird guy with stereotypical child-molester thick glasses. It was really hot in his truck (he probably had the heat on in retrospect) as we drove along a main road and at one point he mentions the heat and that it was ok if I wanted to take off my shirt (for the record, I am a guy). I said no thanks and then opened the door and rolled out into traffic when the truck was coming to a light. Thank god the door handle hadn't been removed or anything.
Bonus: I hitchhiked around a year later and the exact same guy pulled up and asked me if I wanted a ride. He didn't recognize me and I said no, and realized at that point that he must do this kind of thing often. I never hitchhiked again after that day.