i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
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.
Fluxbox - Fluxbox is a window manager for X that was based on the Blackbox 0.61.1 code.
awesome - A dynamic window manager for the X Window System developed in the C and Lua programming languages.
Xfce - Xfce is a lightweight desktop environment for UNIX-like operating systems. It aims to be fast and low on system resources, while still being visually appealing and user friendly.
qtile - Qtile is a full-featured, hackable tiling window manager written in Python.