It's the future!
Valve sent out information on their upcoming Steam Dev Days event, and one of the planned panels will cover the future of virtual reality hardware. Just talking about it would be too simple for Valve, so they decided to make a working prototype to show off what they see as an affordable version of virtual reality.
Here's what Valve has to say about the panel, "We’ve figured out what affordable Virtual Reality (VR) hardware will be capable of within a couple of years, and assembled a prototype which demonstrates that such VR hardware is capable of stunning experiences. This type of hardware is almost certainly going to appear in short order, and the time to starting developing for it is now. This talk will discuss what the hardware is like, and the kinds of experiences it makes possible. A few attendees will be randomly selected to try out the prototype following the talk."