At the time of publication the eleVR player was a first of its kind: a 3D fully spherical virtual reality video player for your browser.
The player: http://player.elevr.com/
Default video is The Relaxatron, or open your own video (equirectangular mono or top/bottom stereo both work). Works in webVR and phoneVR, or use a regular browser and use WASD E/Q to look around.
More about this project: http://elevr.com/introducing-the-elevr-web-player/
Code and documentation: https://github.com/hawksley/eleVR-Web-Player