I witnessed (I really need a dash cam) a tumbling crash about 250' ahead of me on the highway. Some dumbass, in a full-size pickup, decided that he was going to make the exit, while he was 3 lanes away. He nearly made a 90 degree turn and almost made it there, when a silver BMW Sedan smacked into his rear quarter panel. The back of the truck spun around, slid up the guard rail, launching him into a pirouette, then landing nose first and tumbling horizontally for two rounds. He somehow landed on his wheels and just sat there motionless in his seat. I wonder if he knocked himself out.
I've seen at least one crazy wreck a year, for the past 5 years, including a postal truck slamming into a concrete barricade and bursting into flames. The driver walked away, unscathed.