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).
pearOS
pearOS is an Arch-based desktop Linux distribution which features a macOS-like theme and icons on top of the KDE Plasma desktop. Some of the distribution's features include a custom system installer called pearOS Installer, a pearOS welcome application, and the GNOME Files file manager.