6v6gt: There are also some interesting Nano clones for the price of a small beer. The Robotdyn has USB micro connection and an onboard 800mA volt and 800mA 3.3 volt regulator. It is fully breadboard compatible once you solder on the headers (or pay an extra few cents for the ready soldered version). I'll be getting a few of these for the projects I power from mobile phone travel chargers.
For reference, uses the CH340 if that's an issue to anyone.