Arduino Pro Mini 328 - 5V/16MHz

You need to wedge an Arduino into a really tiny spot? Simple - just use a SMD '328 IC. Oh... you want a reset, and voltage regulator too? Why didn't you say so!

Try this - the super-flat SparkFun Arduino Pro Mini, featuring a full 5V design running a ATMega328 at 16MHz. Mind you, there's no headers and USB interface - you have to wire it up yourself, and have an offboard USB-serial cable to program it with!

Features:

• ATmega328 running at 16MHz with external resonator (0.5% tolerance)
• 5V regulator
• 150mA maximum output
• Over current protected
• Reverse polarity protected
• DC input 5V up to 12V
• On board Power and Status LEDs
• 18x33mm (0.7" x 1.3") footprint
• 2 grams! (0.07oz)

Note: Unlike most other Arduino development boards, this one has the USB connection is off board
Resources:

• Arduino Pro Mini Homepage
• Getting Started Tutorial