In the early 20th century, a strange spectator sport flourished in America: train crashing. They were so popular that one man, Joe "Head-on" Connolly, staged 73 crashes (destroying 146 trains) between 1896 and 1932 at state fairs and other large venues.

Those days are long gone. Engineers (the design kind, not the train-drivers) who want to observe a crash can run perfectly safe, highly accurate virtual collisions on a computer screen.