UV Tattoos as Possible Password Storage for Implantable Devices

In the beginning of the month New England Journal of Medicine published an article detailing the security risk of wireless controlled implantable devices such as pacemakers and defibrillators. Researchers at Microsoft have proposed a possible solution that would allow doctors to still access the device if needed while the patient is unconscious: tattoo the password onto the patient with ultraviolet reactive ink. That way the password is only visible using a UV lamp, or if the patient walks into a really cool teenager's bedroom.