I’m the proud recipient of the All Time Stupid Time-Savers award for my kitchen mishap:
I was baking brownies one afternoon, and decided "Oh, why clean a Cuisinart for a cup of chopped nuts? I’ll just use a chef’s knife and a cutting board." Note: round hazelnuts and very sharp knives are not your friend.
I managed to sever two tendons, a nerve and the vein that drains the hand, then had the presence of mind to grab a forest green kitchen towel (blood won’t show up that way) and drive 30 miles to the nearest ER.
Microsurgery, $15,000 and untold embarassment later, I’m the proud owner of a right hand with diminished sensation, which is actually really handy in the kitchen, as I don’t have to worry about using potholders. I just grab the hot stuff now and if I smell something resembling well-done pork, I put the item down again.