Re: Wiimote :)
Absolutely. Did this years ago with a head-tracking eMagin Z800 headset.
Playing Oblivion with a Wii Balance Board for motion (so you're skateboarding around town :)), Wiimote + Nunchuck for left/right arm (or even pull-back w/button pressed to notch an arrow, release to fire). And head-tracking so you always look where you're... well, where you're looking.
The only serious problem was that you couldn't look and aim independently. Which should be pretty simple to sort in an all-3D game (so anything from Quake onwards).
Another little issue was that I needed to have a multibutton mouse to select which kit combination I was using, and remembering that in the middle of a battle was a PITA. But again, a software fix to output which weapons/shields/spells/etc are equipped over USB/serial/etc would sort this.
If the Rift can bring this sort of tech into the proper mainstream, good for it! I'll certainly be buying one :D