A BSD-based OS project that aims to provide an experience with MacOS
Blazingly Fast & Customizable Linux distribution
AO RTOS is small real time OS based on Active Object concurrency model
Free real-time operating system designed for microcontrollers
qnutCNC is a program to control the ethernut development board
4.4BSD-based UNIX-like operating system for CNC / machine control
The CK 64-Bit Kernel Operating System