Depends on MS Windows? Me, too. But here is something you want to know…
// from Reactos website.
ReactOS® is a free, modern operating system based on the design of Windows® XP/2003. Written completely from scratch, it aims to follow the Windows® architecture designed by Microsoft from the hardware level right through to the application level. This is not a Linux based system, and shares none of the unix architecture.
URI to ReactOS: http://www.reactos.org/