I went to a nerd school so mine's more scary than disgusting. An intern was cleaning after a science experiment with magnesium and hydrocloric acid (as well as a mixture of other materials). Rather than properly dispose of the chemicals he poured them down the toilet, slipped, and fell head-first into the bowl. He came out with horrid chemical burns and [i]melting[/i] skin and had to be rushed to the emergency room. He came out with a permanent burn scars down his left cheek and eye. Not as bad as what you see in acid attacks but he had slight discoloration of the skin.