TKaraoke can output multiple video windows for the same song. The video windows would sync with each other. This feature is useful for users with 3 or more TVs. Each video window can be undocked from the main window and can be expanded to fullscreen mode. This feature has been researched for Professional Edition but might be available on Free Edition of TKaraoke.
Imagine having 4 video windows on 4 corner of a restaurant :)
Sample Screenshot:
