The Arduino Nano is a small, complete and breadboard-friendly board based on the ATmega328 (Arduino Nano 3.x) orATmega168 (Arduino Nano 2.x). It has more or less the same functionality of the Arduino Duemilanove, but in a different package. It lacks only a DC power jack and works with a Mini-B USB cable instead of a standard one. For more information.
Powered via the Mini-B USB connection
14 digital pins on the nano
8 analog inputs all with 10 bits of resolution