Sparkfun's new product showcase today has some cool gear that's useful for UAVs, In the video above, they demonstrate how to use the AttoPilot current sensors to measure voltage and current consumption in a quadcopter. APM supports this current sensor board, too, and now Sparkfun has several different versions for different currents:
The AttoPilot boards provide a simple solution for reading voltage and current into your microcontroller. Now in addition to the 90A version, we also have 45A and 180A versions as well. Voltage and current values are easily read into your favorite microcontroller and we've included example code for Arduino on the product pages.
Sparkfun has also updated its "9DoF" IMU board (below) to use the new Invensense 3000-series gyro, which combines XY and Z into one chip to make for a smaller board.