Going to work one day, after a test in physics, head in the clouds, I walked straight into an open hatchback door of a minivan. Hit my forehead so hard on the door, that I bit down and snapped one of my front teeth out. Everytime I took a breath the air hit the tooth root and sent me flying. Had to go for dental work and for a couple years, I was getting that bugger fixed. A lot of money invested into one tooth, for something very stupid.