Best of Experiments with HTML5 & WebGL

THREE.SimpleDatGui - A Pure WebGL User Interface for THREE.js
A graphical user interface which is rendered within the THREE.js scene so that it can be displayed in Oculus Rift for both eyes.

You may start here with desktop browser.

Extremely Fast and Simple WebGL Motion Detector to Rotate 3D Graphic
Demonstrates how the browser captures the video signal and compares subsequent frames to detect motion of the user.

You may start here with desktop browser.

Finite Element Method Running in the Browser and Uses Device Orientation
Minimal Finite Element Method (FEM) Simulation running in a web browser and uses device orientation signals. 

You may start here with mobile browser.