There are two demos below. The first is a Google Cardboard demo that allows you to move around using a bluetooth controller or keyboard.
https://view-only-vr.glitch.me/
The second demonstrates interaction with an identical virtual space, adding real-time, full-body motion tracking and basic physics
The physics are not complicated- the hands and feet of our character have spherical colliders to allow them to push/kick other objects, but this simple direct interaction turns an otherwise boring virtual space into an effective playground.
Not pictured in the video is Mikel walking around in SL402 wearing this gear: https://cdn.uploadvr.com/wp-content/uploads/2016/04/perception-neuron-featured.jpg
