The OS561 operating system based around FORTH/Java. The OS is to run on a VHDL chip OpenHardware design called the Minon, but could become available for other platforms. The unique point of the design is a revolutionary data compression technology.
CJet eXTreme OS is a new project to develop a cross platform operating system with a native application interface designed to make it easy to develop for several architectures at once.
The Isis OS Project Is a Controlled Project to Develop An Advanced Modern Operating System!
MDF is microkernel operating system. Module architecture minimalistic design.