As you have probably already seen, the Xbox 360 controller went through many revisions leading up to its release. This controller, codenamed Krypton, was a late model prototype that is nearly identical to the retail 360 controller. This particular controller, while in poor condition (the joystick caps are missing, along with a fray in the wire), still shows some of the differences leading up to that quick release of the 360.
Gone are the early buttons, instead having a retail configuration. But notable is the lack of the standard guide button, instead replaced by a simple white button. The other main difference is that the left joystick, d-pad, and right joystick all have indented letters indicating their name, which is unseen in the final controller. This may not be the most exciting of prototypes, but it is still pretty cool. Check out the full gallery after the break!