There's nothing quite so enlightening as a solution to a problem you didn't realize you had. Cronus, a little USB stick that the company promises will "change how you look at gaming." While the little USB adapter's functionality isn't quite so grandiose (same goes for the company's assertion that it's "the greatest invention in gaming since the controller"), the peripheral offers up an interesting proposition -- being able to control your Xbox 360 with a PlayStation 3 controller -- and the other way around. Oh, and Wiimotes are in the mix, as well.
The Cronus is a black USB dongle with a small single digit display on the top and a USB input on the rear. Plug it into the console of your choice, sync it up and you should be good to go. More here.