Well, i was thinking about this, and i have saw it in many things, for example the "Return" Trailer, where the Jedi knight takes the double sided light-saber and his own, then turns the one end off and fights with dual light sabers, this is a unique idea, and it could be used with the sith assassin and Jedi shadow. Maybe unlocking new attacks too. This will probably be quite hard to implement, but it would be very cool indeed.