Fedora
Fedora Linux (formerly Fedora, formerly Fedora Core) is a Linux distribution developed by the community-supported Fedora Project and owned by Red Hat. Fedora Linux contains software distributed under a free and open-source license and aims to be on the leading edge of such technologies.
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).