|this is cool!
i had somthing similar in mind...
Battle Ball for Sailor Training
The Navy Newstand has a quick run-down of the VirtuSphere -- a nine-foot plastic ball that sits on wheels enabling unlimited rotation in any direction. It makes virtual reality feel a whole lot more real.
The Office of Naval Research (ONR) is developing systems like VirtuSphere as part of a program called Virtual Technologies and Environments (VIRTE). A user, wears a wireless head-mounted display (HMD) that displays landscape, and can update continuously as the service member moves, by detecting changes in orientation. Much of the work with VIRTE focuses on the needs of the Marine Corps.
The ONR selected VirtuSphere for the VIRTE program last fall. The VirtuSphere allows the trainee to walk, run, and crawl in any direction, adding a further dimension of realism to virtual training. The ball can be disassembled, the entire kit fits in a car for transportation, and it weighs less than 500 pounds. There are a number of videos available for those with some time to kill.
Besides the military training application, there are obviously a ton of other possibilities for this product. The company is based in Redmond, Washington, so I hope that they're working with the Softies to hook this bugger up to an XBox 360. Sort of an XBox 3603.