Accelerometers / Gyros

Hall sensor with a digital display module (speed / counter / timer)

GY-511 LSM303DLHC e-Compass 3 Axis Accelerometer Magnetometer Module Sensor

MMA8451 GY-45 Module Digital Triaxial Accelerometer Precision Tilt for Arduino

MMA8451 GY-45 Module Digital Triaxial Accelerometer Precision Tilt for Arduino  

GY-81-180 Flight control module 10DOF ITG3200/ITG3205 BMA180 HMC5883L MultiWii MWC module

GY-50 L3G4200D 3-Axis Gyroscope Angular Velocity Module

Sharp IR Sensor