Here it comes: LiFi !!  (Did I tell you about this already -- yes.)  Visible Light Communication is next-generation WiFi.  Headline: Researchers at U Mass use the body to harvest waste energy to power wearable devices. They have invented a low-cost, innovative way to harvest the waste energy from VLC by using the human body as an antenna.  This waste energy can be recycled to power an array of wearable devices, or even, perhaps, larger electronics.  (Didn't I write about wearable batteries years ago -- because the thought hit me, not because I ever read about it.)

Wait until people compete to be the most electro-productive ... Read more here.