Remember EnOcean's batteryless / wireless light switches on display last year? Don't sweat it, neither did we. Still, that hasn't stopped EnOcean from experimenting with battery-less sensors which harvest electricity from vibrations (pictured) and temperature differentials. According to EnOcean, their prototype thermal-differential sensor attached to say, a water pipe, can harvest up to 50-milliwatts as long as one surface is 3-degrees Celsius higher or lower than the immediate environment. While that pales in compaison to batteries, it's still enough power to transmit a tweaked RF signal as far as 300-meters in an open warehouse or 30-meters through walls. Nearby sensors can also act as relays to extend signal transmission. Link the sensors with a thermostat and you can create micro-climates around the home; link 'em to a home automation system and control your house without the need to run power and Cat 5 / WiFi everywhere. Now someone get those X10 spammers home automators on the horn, we smell a business op.