ST Microelectronics (www.st.com) as released the Primer 2, a cell phone sized development platform that includes a color touch screen, joystick, and several connectors.

PRIMER 2 dev platform

The Primer 2 is an update from the original “circle” unit, the Primer 1, which inspired the Circle OS, an open-source software framework allowing easy development.

Primer 1 ("the circle")

The STM Primer2 is available for around $50.  A price compairson showed Mouser to be the cheapest vendor to sell the units directly.   Be warned, the direct vendor channel versions are limited in the code size that can be debugged.  STM  must be contacted directly for the full code-space versions.