The Arduino Nano is a small, complete, and breadboard-friendly board based on the ATmega328 (Arduino Nano 3.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.
Operating Voltage: 5 V
Flash Memory: 32 KB of which 2 KB used by bootloader
SRAM: 2 KB
Clock Speed: 16 MHz
Analog IN Pins: 8
EEPROM: 1 KB
DC Current per I/O Pins: 40 mA (I/O Pins)
Input Voltage: 7-12 V
Digital I/O Pins: 22 (6 of which are PWM)
PWM Output: 6
Power Consumption: 19 mA.