That's a current work-in-progress aiming at rebuilding the complete Physics Body Editor engine to an HTML5 verison.
Currently, the server uses Node.js as its runtime, but the application is actually fully client-side, thanks to AngularJS and all these awesome javascript libraries.
- Install node.js (http://nodejs.org/)
- Open a command prompt in the project directory
- Run npm install
- Run node server
- Open a browser and go to http://localhost:4000