It plugs the jewelry in the skin, or else it loses power again. (Via)
"Hey, can I borrow your charger?"
"Sure, I'll hook you up."
(Hooks actual charger into veins.)
Naomi Kizhner created a theoretical, but totally possible, line of invasive jewelry called "Energy Addicts" that finally makes extreme piercings have a value greater than scaring potential in-laws. It harnesses the power of you.
The jewelry is pierced into your skin and then utilizes the body's natural abundance of kinetic energy created by simple, involuntary movements, such as flowing blood or blinking. A small wheel inside the jewelry is turned and the energy is converted into electricity for much more important actions, like powering your phone.