A YouTube user known as undertakencodes, posted a video of his Xbox 360 running Snes9x, a freeware Super Nintendo emulator.  The video looks legit except for the light on his Xbox 360 coming on mysteriously before he inserts the disc.  The exploit does not require any modification of your Xbox 360 and runs off the Xbox emulator.  At this time the user has not posted any additional details.  This could open the door to homebrew on the 360!