After seeing this video, I'm about ready to put money on the Virtuix Omni
when it hits Kickstarter. The Omni is an omni-directional treadmill meaning you can go any direction, yet stay in one place. The setup looks to have a waist strap that feeds back some info to the computer and the platform that lets you walk in any direction.
Here, they are pairing up an Omni with an Oculus Rift and playing Team Fortress 2 to provide looks like an awesome VR experience. It also looks like a great way to get some exercise as well as play games at the same time. Virtuix is looking to bring this product to the consumers and their Kickstarter should be up soon. I'm already clearing out an area in my game room for this.