Ben Heck has come up with a one-handed Xbox 360 controller for that added difficulty level after you have mastered a particular game using both hands. He has introduced a semi-intrusive joystick that does away with the need for the left side of the controller, while a mechanism thrown in on the rear of the controller will help one manage all the bumper action. Definitely not one of the prettier mods he has delivered to date, but it ranks high on the interesting factor.