The GreatFET One board created by Great Scott Gadgets is designed around an LPC4330 dual-core microcontroller from NXP. This MCU has an ARM Cortex-M4 core as well as a Cortex-M0. The GreatFET One has the same size as an Arduino UNO board and, like Arduino, it is an open-source and open hardware design. The board comes preloaded with a special firmware that allows the MCU to be controlled from a host computer, and that's dead easy using an extensive Python library.

 
 
Me too, I want a GreatFET One board...