Window managers

GUIs see contention for 3 resources: screen area, especially with things that want to always remain visible, places to click based on Fitts Law, and input events, like keyboard and mouse. It could include sound and microphone. It could be generalized to simply input and output bandwidth.

I would like to see a window manager that worked in modes like vi. In one mode, keystrokes and other input events are sent to the application with focus, in another they are sent to the window manager.