OS9exec - execution environment for OS-9/68k user-mode programs on MacOS9 / MacOSX / Windows and Linux host OS. (OS-9 is an RTOS of Microware/Radisys)
Achelous is attempt to clone Mac OS X for the Intel X86 Chipset. There are currently two teams working on the project: the Kernel team and the GUI team.
MOOnix is a UNIX-like internet TCP/IP "OS" written in MOO. MOOnix will allow for active programming, which will allow multiple programmer's clients to automaticly update the source when there is a change. Other users can simple use MOOnix as a UNIX shell.
We are developing a suite of software to control USB I/O devices. Initially the support will be for Windows and Linux hosted Human Interface Devices (HID) although hopefully this will extend to virtual comms. port control in the future. API coming...
vMac is a free Open Source Macintosh emulator that is available for Linux/X-Windows, Win32, DOS, MacOS, and more.