The Lumina Desktop Environment is a lightweight system interface that is designed for use on any Unix-like operating system. It takes a plugin-based approach, allowing the entire interface to be assembled/arranged by each individual user as desired, with a system-wide default layout which was setup by the system administrator.
Xfce is a desktop environment for X11 and Unix-like systems. It's comparatively lightweight and low on system resources, yet provides a modern and customizable interface. It includes a window manager, a panel and taskbar, file management, system and desktop setting tools, power management, intuitive virtual desktop switching, and a media player amongst other features.