The 9DOF Sensor stick is a very small sensor board with 9 degrees of freedom. It includes the ADXL345 accelerometer, the HMC5883L magnetometer, and the ITG-3200 gyro. The 'stick' has a simple I2C interface and a mounting hole for attaching it to your project. Also, the board is a mere 0.036" thick (0.093" overall), allowing it to be easily mounted in just about any application. Project description, more information and ordering can be found at https://www.sparkfun.com/products/10724 Datasheet: http://www.sparkfun.com/datasheets/Sensors/Accelerometer/ADXL345.pdf Datasheet: http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Sensors/Magneto/HMC5883L-FDS.pdf Datasheet: http://www.sparkfun.com/datasheets/Sensors/Gyro/PS-ITG-3200-00-01.4.pdf AHRS/Head-tracker Tutorial: https://dev.qu.tu-berlin.de/projects/sf-razor-9dof-ahrs/wiki/Tutorial