"StumpWM is a spiritual and visual descendent of Ratpoison,and shares many basic key commands. There are, however, some key points that set it apart from RP and, indeed, most/all other window managers [...] The ability to customise is virtually endless, and the interface is flexible and elegant. While the idea of using Lisp to customise your window manager might sound intimidating, StumpWM's methods of doing this are quite elegant and generally simple to do. If you've ever worked with customising Emacs to any degree, there's little to fear."