My friends and I would try to find things to do that didn't require much money, as many high school kids are wont to do. One of the pasttimes we discovered involved an overpass. We would take bricks, tie them with twine, and dangle them over the overpass in front of passing cars. We'd hold it there until the car got right up to it, and then we'd pull it back (so we wouldn't cause any real damage.) Since twine can sometimes get hard to hold, especially when you're outside in hot weather, we would wrap the twine around our wrists to keep a better hold on it.
One day, while we were playing our game of modified chicken, my friend put his brick down in front of a Semi truck. Well, the semi was going a bit faster than my friend realized, and with the extra height, he was unable to pull the brick up fast enough. It ended up hitting a cross bar on the top of the cab and wrapping itself around. The driver, having slammed on the brakes because of the brick floating in front of his face, was unable to stop quickly enough. The torque from the jerk of the twine on my friend's wrist pulled his whole arm right out of the socket. He freaked out and needed emergency care, we didn't know what to do, because we'd never heard or seen anything like that before, and the driver was beside himself watching a severed arm flapping in front of his truck.
The paramedics arrived and took our friend to the hospital, and we stayed with the driver to talk to the police who arrived around the same time. We told the officer of our game, and were ready to face the consequences of our actions. Imagine our surprise when the officer turned and arrested the truck driver.
When asked why the officer was arresting the driver, the officer replied: "Armed robbery."
(This is not a true story)