with your medical history encoded upon it. Not a new idea, not a good one either. But if you want to drive tractors you will need a fed drivers CDL. If you want to travel outside the USA you need passport to get back in. If you want to own a machine gun you need a federal firearms dealer license. Somewhat ambivilous(not quite ambivilent) on this one but against if required to carry it at all times.
Papers please.
thanx,