Microsoft seems to be riding the patent steamroller these days. Their latest patent involves a method of powering small devices or Personal Area Networks (PANs) using current transmitted through the user’s skin.

Microsoft patents body power - ZDNet

“As a result of carrying multiple portable electronic devices, there is often a significant amount of redundancy in terms of input/output devices included in the portable devices used by a single person,” says the filing. “For example, a watch, pager, PDA and radio may all include a speaker.”

To reduce the redundancy of input/output devices, Microsoft’s patent proposes a personal area network that allows a single data input or output device to be used by multiple portable devices.
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In its filing, Microsoft says its work addresses wearable devices that are too small to have any kind of interface or even a battery, such as earrings. The company proposes using pulsed AC or DC signals to power the devices. A 100Hz signal could be used to power one device, while a 150Hz signal could be used to power another, the company said, and data signals can be modulated on top of these power signals.

Furthermore, Microsoft said, the physical resistance offered by the human body could be used to create a virtual keyboard on a patch of skin. And just to make sure it has covered all its bases, the filing concludes with a reference for Fido.

“It will be apparent,” it says, “that the body may be that of a wide variety of living animals and need not be limited to being a body of a human being.”

At least in this case Microsoft doesn’t appear to be trying to patent a common technology that has tons of prior art out there. It does sound eerily similar to some of the cyberpunk fiction I’ve ready over the years, though.