This project is a great example. [Scott Daniels] takes a look at the other voltage measurement options available to AVR chips used by Arduino.

He further explains that, with the Arduino Uno, you can remove the reference capacitor from the circuit, and simply use the stray capacitance present in the board and microcontroller, which can be ...

The ArduIMU V4 is an Arduino based integrated measurement unit that offers a complete wireless sensor module that started as an open source project by 3DRobotics back in 2007.