esp8266
- Small wifi electronic module ESP-01(WIR04001251) and ESP-03(WIR04001252)
http://www.hobbytronics.co.za/p/930/esp8266-serial-wifi-wireless-transceiver
3D wifi map http://hackaday.com/2015/02/17/mapping-wifi-signals-in-3-dimensions/
github project for ESP https://github.com/cnlohr/esp8266ws2812i2s
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