Official Google Australia Blog: Google Search for your socks
These new bluetooth-enabled socks are fitted with thin LTE beacons that wrap around the top of your lower calf, just like the coloured stripes you’d see on traditional socks. If you can’t find one sock, you can press the beacon on its pair and let the Google Search app on your phone pinpoint its whereabouts. The missing sock will then sing this song to help you find it.