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).
ZimaOS
ZimaOS is an independently-developed, Linux-based operating system for personal servers and network-attached storage (NAS) devices. It features system-level support for remote access, RAID configuration, over-the-air (OTA) updates, and a browser-based user interface for managing the server.