You need to install Compiz Config Settings Manager:
"sudo aptitude install compizconfig-settings-manage"
and launch it from Dash(main button) by filtering "compiz".
select in the "Window Management" section a "Put" item. With that enabled, you can set a shortcut key in the "bindings" tab for "Put to Next Output". By default, it's disabled, but is easy to set.
No restart is required (at least on Ubuntu 12.04 x64).
If you have two monitors - this combination will work like swap of window location on monitors.
My default is "Cntl+~".