These two are the guts of my interface plans:

Arduino Leonardo

The Arduino Leonardo is an awesome board. It’s quite similar to the Arduino Uno, which I’m quite experienced with, but the biggest difference (and reason I’m getting it) is that it can emulate HID’s in Windows, meaning it can trigger mouse movement/click events, as well as keyboard input. I plan to either directly map it to a mouse, or have different measurements trigger innocuous keystrokes that can be picked up in the background by something like vJoy and mapped to joystick inputs.

HMC5883L 3 Axis Magnetometer

This magnetometer is really the engine of my interface ideas, and interfaces very simply with the Arduino over I2C (there’s even great code examples and demos by the SparkFun crew – don’t you love them?).

I’m also planning on adding a 4×20 character LCD display so I can eventually package it up and just plug it in as a native HID device; no need for serial listening to see the calibration prompts (get mag field strength when finger is out, in, pressed, lifted, etc.). We’ll see how this goes. If it pans out, I may shrink it down even further and try to do away with the big bunch of Arduino headers/just opt for the ATMega.