Monkeygirl has a post about finding Chinese food detritus found in an obese person's skin folds and it reminded me of one of my favorite stories from when I used to work on the floors, before I came to the ED.
We got a lady who was admitted because her many decubiti needed debriding. She had several of them, and was so fat, she was as wide as she was tall. I took all of her clothes off and prepared to dress and document all of her wounds.
Part of her abdomen and one of her breasts were greenish; I thought she had a fungus or something. I started wiping it off and followed it up to a skin fold, where I found . . . a quarter, a dime, and a penny--that was oxidizing and was turning her skin green. There were perfectly round sores underneath each coin. The smell was lovely too. Yum.