Joe Desbonnet was looking for a cheap and easy way to transfer data from an Arduino to an Android device. The hack he devised requires only a 1-meter length of wire wound into a coil, a resistor and diode. He writes:
This is a little hack that allows very low bandwidth communications in one direction for practically no cost. It’s not practical for most applications, but I thought the idea was sufficiently interesting to explore. This article describes how to implement a very low bandwidth one way communication channel between an Arduino (or any other microcontroller) and an Android device using nothing more than about a meter of magnet wire, a resistor and diode. Links to a software sketch for the Arduino and the Android source code is included.
Cool and imaginative!
Thanks Joe! Via the contact form.