The Arduino development platform has introduced millions of people to embedded programming.  With an easy to use development environment and a bunch of libraries that make it easy to get up and going quickly, there isn't a better way to have fun with microcontrollers.

This platform is the Leonardo variety, based on the Atmel ATmega32u4, and is a genuine Arduino manufactured product.  The Leonardo gives you a few more I/O pins and is nearly completely surface mount.