ESD has just finished a project using the iPhone accelerometer - the LIS331DLH. Sparkfun sell a zillion accelerometers but not the one used in the iPhone. This device made by SGS-Thomson uses very low power (~0.25mA) and can measure 3 axes to 16bits. Also, it can be interfaced via I2C or SPI. Email us for more info about this LIS331DLH accelerometer test board.
