Half Life 2 on Oculus Rift should look something like this.
I admit, I was still somewhat on the fence about Oculus Rift - I've had my heart broken by promises of virtual reality before - but this video of Nathan Andrews' head and gun tracking mod for Half Life 2 has made a believer out of me.
The mod, designed for the (hopefully) impending release of the kickstarted VR headset, lets Freeman lean, free aim and lurch around the battlefield like he's knocked back half a bottle of scotch. It remains to be seen if the gameplay holds up without a trusty mouse, but the leaning and aiming does look impressively natural. Though Andrews doesn't demonstrate it, you can even shoot off the screen by looking one way and firing the gun in another.
In this video, Andrews is using a set of Hillcrest Trackers (the same type of movement trackers used in John Carmack's Doom 3 BFG Oculus Rift demo) but he intends to update the mod to work with the official Rift sets when they're released later this year. Assuming you have your own headset and tracker setup, you can download the mod and try it out right now.
The gun in the video is a Top Shot Elite IR gun designed for the Cabela's Dangerous Hunts series. Movement is controlled by an analog stick on the gun, while leaning and aiming are controlled by the two movement trackers.
I generally fall into the grumpy old man cliche when it comes to motion controls. The only thing I shake is my fist, usually at you appalling young-uns with your your Wii motes and your Kinects, but this video has sparked something resembling genuine excitement in my withered heart. The only thing the game is missing is the option to headbutt enemies by jerking your noggin forwards.
"No. You pick up that can."