Hacker Nathan Seidle at SparkFun Electronics has hacked his Nike+iPod pedometer to make a wireless car key.The reason I believe he gives is that he hates keys! So Nathan Seidle rolled his own car-opener with a Nike+ dongle and receiver, an Arduino board, a Nike+iPod Serial to USB Adapter and some creative sabotage.
The only little problem he faced was that the range of the Nike+ was 50 feet so the trouble was the car locking and unlocking when in that range.To correct that he simply added tin foil wrappings which almost halved the frequency.

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