Here's a more complete demo of Nebula3 running in Javascript+WebGL via emscripten:
http://n3emscripten.appspot.com/
You can move/rotate the camera with mouse-button + dragging, and add more dragons with the Up key.
Each dragon evaluates its own animation on the CPU, despite that I think that the resulting performance is pretty good.
You can compare the performance to the Native Client version here (requires Chrome):
https://chrome.google.com/webstore/search/nebula3
Have fun,
-Floh.
