ReactOS 0.4.2 Released: Supports Linux Filesystems, .NET Applications, and Doom 3
Found on Slashdot on Saturday, 27 August 2016
Continuing its rapid release cycle, ReactOS has unveiled version 0.4.2 of its free "open-source binary-compatible Windows re-implementation."
ReactOS is free. You can boot your desktop or laptop from it. It looks like Windows (a 10-year-old version, anyway), so you already know how to use it.
For a couple of core developers, that is an amazing work.