i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
VMmanager - VMmanager is a QEMU/KVM server virtualization management software, which presents perfect tools for creating virtual machines, providing VPS services, and building cloud infrastructure.
dwm - dwm is a dynamic window manager for X. It manages windows in tiled, monocle and floating layouts. All of the layouts can be applied dynamically, optimising the environment for the application in use and the task performed.
Virtkick - Virtkick is a Software as a Service VPS control panel and your company’s storefront.
awesome - A dynamic window manager for the X Window System developed in the C and Lua programming languages.
oVirt - oVirt is a virtualization management application.