We're building a time of flight depth sensing camera specifically for virtual reality hand-tracking and input. We just launched the project on Kickstarter:
The camera will capture a 3D point cloud across a 110 degree field of view and at a range of 10-70 cm. We're combining this with the world's most robust skeletal hand tracking software to bring hands into VR for input.
Here's a video of how you might use this input in games like Spectre, Technolust and Ethereon.