ReactOS is the best known Windows XP alternative. Imagine running your favorite Windows applications and drivers in an open-source environment you can trust.
ReactOS 0.4.1 Changelog
Due to the brief period of time between the two releases, 0.4.1 is ultimately a refinement of what was in 0.4.0. That is not to say that there are no new features of course, and a few highlights of both categories are listed below.
- Activation Context - A fix that came in just a tad too late for 0.4.0, this resolved a problem in the loader that prevented applications depending on various versions of the MSVCRT library from working properly.