Fluxbox - Fluxbox is a window manager for X that was based on the Blackbox 0.61.1 code.
IceWM - icewm home page . Bug Tracking. If you have a patch, a bug report or a feature request to submit, please do so at the icewm project page at SourceForge.
Openbox - Openbox is a highly configurable, next generation window manager with extensive standards support.
KWin - KWin is a window manager for the X Window System, and is in the process of becoming a Wayland...
JWM - Also known as Joe's Window Manager. Created in 2003, one of the default window manager for Puppy Linux, and actively updated by Joe, its creator.
qtile - Qtile is a full-featured, hackable tiling window manager written in Python.