On suggestion from my triathlete brother, I applied KT Tape to that calf I sprung out of whack while running last weekend. The stuff works! It's stretchy, kind of like a stick-on Ace bandage, gives support for the injured muscle, and gives it a chance to rest and heal. It's probably over-used on non-injuries (search on "KT Tape snake oil"), but for a genuine, minor injury, this stuff is the stuff. If you're not sure how to apply it, remember that youtube is your friend.
But using it for a performance enhancement on uninjured parts seems nonsensical. I mean, if a stretchy skin-level membrane improved performance, wouldn't we have already evolved one?