doub has been working on a development board for Lua programming:
So this project is about packing a relatively fast microcontroller, but not complex enough to require a high level OS (like Linux for SoC-class chips), with a big RAM chip. I picked a STM32F427, because I have some experience with the STM32 family, the core is a Cortex-M4F (floating point will help running Lua), and it is one of the few Cortex-M microcontrollers with an SDRAM controller. SDRAM is desirable over SRAM because it’s much more dense and there are 256Mbits (32Mbytes) chips available for a few dollars.
Via the forum.