SmartOS
SmartOS is an open-source UNIX-like operating system based on illumos, a community fork of OpenSolaris. It features four technologies - ZFS (a combined file system and logical volume manager), DTrace (a dynamic tracing framework for troubleshooting kernel and application problems), Zones (a lightweight virtualisation solution), KVM and bhyve (two full virtualisation solutions for running a variety of guest operating systems, including Linux, Windows, BSD and Plan9).
VailuxOS
VailuxOS is a German, desktop-oriented Linux distribution based on Ubuntu's long-term support (LTS) branch or Debian's "Stable" branch. The project's primary goal is to make the transition from Windows to Linux as seamless as possible by maintaining familiar ways of working and workflows.