uric acid is also very good for your skin. Most (probably all) commercial products like Eucerin use a synthetic variety (I think), but a massage therapist told me that her grandmother bathes her feet in her diluted urine because it softens the skin. Also, I have a home-spa book that recommends that if it doesn't gross you out too much.
I have not done the pee foot-bath, but I have to admit that my own pee does not really gross me out at all.
