i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
WindowBlinds - WindowBlinds is a computer program that allows users to skin the Windows graphical user interface.
awesome - A dynamic window manager for the X Window System developed in the C and Lua programming languages.
Cairo Shell - Cairo is a desktop environment for Windows.
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.
bbLean - Alternative Windows shell