Well tech tinkerer Joe Desbonnet has whipped up what he dubs "poor man's NFC" using an Arduino, some magnet wire, and any compass-equipped Android smartphone (which is almost all of them).

[Mirko] solved this by encasing the Arduino inside a closed, grounded metal box with only the required wires sticking out.

Arduino-fanciers Oomlout have put together a neat control box for the popular prototyping board, complete with five potentiometers and three switches. There's also a software… ...