Open Source Ruby Window Managers

batalert (aka Battery Alert) is a tool, written in Ruby, to notify the users when their battery is either under-charged or over-charged. Just consider installing it and put it on cron so that you never have to worry about running out of battery in midst of your work! This is originally intended for WM users who don't get battery notifications by default, but can be used by everyone who sees its worth! Batlalert upon being set up, shall notify you when to put your battery on charging and when to unplug it too. Whilst notifying so, it also numerically mentions your battery percentage at that particular moment.

Aegis is a highly configurable, scriptable X window manager.

The Free-POSIX Common Desktop Project exists to create an open standard for free Desktop implementations.

Continuation of Waimea window manager with planned support for extensibility with Python (initially) and Ruby/Perl further down the road.

subtle is a grid-based manual tiling window manager with a strong focus on easy but customizable look and feel. In comparison to other tiling window managers, subtle has no automatic tiling of the screen size in any way.