I've been meaning to work on a tether for fc, a means for it it to interract with the physical world.( I mean, that IS the whole point ) 
 
Currently the only "microcontroller" I currently have is a RPI2 which currently has NetBSD installed. I'm working towards three goals right now. 
 
1. Serial communication with DSC PC1500RK security control panel 
2. Analog sensor input such as thermistors( using a MCP3008 ) 
3. Binary sensors such as door reed switches