it's called the "Avenger," and that it's from peripheral maker N-Control, and that it snaps onto your Xbox 360 controller and supposedly "allows for rapid, fluid movements between individual buttons and analogue sticks, allowing gamers to access nine functions simultaneously." Still, even after watching these testimonials -- no idea. Are those mandibles? And where'd all the buttons go? Did the Avenger eat them? With its mandibles?
The attachment will run you $59.99. It will also cost you the chance of us ever looking you in the eye like a normal human being ever, ever again.