It's Here! Chris Odom's Physical Computing & Robotics with the Arduino IDE - Volume One

ATmega328P UNO-Compatible board

$4.50

Important!!! These boards are not plug and play.

You must manually install a CH340G driver or the arduino software won't recognize the board (see video below for instructions).

Once you get over that hassle they are perfectly fine. At the price they are great for those risky projects. Thinking about a sub, rocket or autonomous zeppelin...anything that you might never get to see again...get one or two of these. They program the same and run the same. I use them for economical classroom bots coupled with the equally cheap motor driver board. 
Even ships with some extra header pins and a terribly short USB cable.

The whole playlist using the ATmega328P Uno board