An engineer named Jim Mielke has invented a display that is wireless and powered by blood. The display would be implanted into the body between the skin and the muscle as a tight roll. According to Mielke the roll would then unfurl and position itself between muscle and the skin.
Once unfurled, the display would get its power from the blood. Specifically a small fuel cell would have leads hooked up to an artery and a vein allowing for blood to flow through a blood fuel cell that converts the oxygen and glucose in the blood into electricity.