sdorfehs (pronounced "starfish") is a tiling window manager descended
from ratpoison (which itself is modelled after GNU Screen).

sdorfehs divides the screen into one or more frames, each only
displaying one window at a time but can cycle through all available
windows (those which are not being shown in another frame).

Like Screen, sdorfehs primarily uses prefixed/modal key bindings for
most actions. sdorfehs's command mode is entered with a configurable
keystroke (Control+a by default) which then allows a number of bindings
accessible with just a single keystroke or any other combination. For
example, to cycle through available windows in a frame, press Control+a
then n.