Move windows around a desktop -- and to different desktops -- using only the keyboard?
Moving windows to another space:


SizeUp (still works for me in 10.8)
Spacey (stopped working in 10.7)


Moving windows to another display:


BetterSnapTool
BetterTouchTool
Flexiglass
Moom
Optimal Layout
SizeUp
Spectacle
Window Mover