ReactOS is an open source effort to create a Windows NT 4/2000/XP+ compatible operating system licensed under the GNU public license. ReactOS aims to achieve complete binary compatibility with both applications and device drivers meant for NT and XP operating systems, by using a similar architecture and providing a complete and equivalent public interface.

Homepage: http://www.reactos.com/
Download: ReactOS-0.3.3-REL-iso.zip
File Size: 23.35 MB