NewOS is a free operating system with full source code available, along with periodic binary snapshots. Currently runs on Intel and AMD single and multiprocessor desktops, Sega Dreamcast. NewOS exists to explore some aspects of modern OS design, and to have fun in the process. According to the developer, "I seemed to have collected a bunch of old non-x86 machines that need something running on them. I figure, 'Hey, why dont I just port my OS over?' The rest is history" .....(free).....