Using skin to create a human area network
(Credit:
NTT)
Science just got weirder. Grown right out of a Japanese petri dish, Firmo is NTT's idea of a device that transforms the human body into its own truly personal area network (PAN), allowing people to communicate with devices just by touching them. The Japanese telco giant prefers to call this HAN, or human area network. (And South Korean researchers are working on a technology it calls BAN, or body area network.)
The gadget in question is a card-sized transmitter that cloaks the body with a weak AC field so that when it comes into contact with a compatible receiver, it's translated into signals, according to RBB Today. The potential applications are far-reaching, from making payments to activating your music player with a single touch.
Not surprisingly, the technology isn't cheap: A set of five transmitters and one receiver goes for 800,000 yen, or about $7,620. But frankly, the idea of being constantly charged up raises goose bumps on what this might do to our organs in the long run.
(Source: Crave Asia)


Unfortunately, this approach still focuses primarily on a one-way process AND (as Juniper mentioned) entails a low-level full-body EM field which is going to be an issue of concern for many.
Personally, I think personal ID systems (as one subset of and use for wearable systems) should be interacting with the user's personal environment optically, using line-of-sight multi-transceiver IR devices, with a strong emphasis on "interactive".
Many MANY (more) profitable directions THAT approach would open up.
Ray G