Power beamed to camera via ambient wi-fi signal shttp://www.bbc.co.uk/news/technology-33020523

I didn’t invent the concept of remote power and I certainly wasn’t the first person to realise it’s potential. But I have been banging on about it for years. Low powered devices being powered over WiFi makes sense to me. NFC is a kind of remote power, combine its technology with PoWiFi and the smart watch need never be charged again. At the other end of the scale all electric powered vehicles could get thier power while driving let alone when parked, anywhere.