Unity support for WebGL
Of some relevance is the announcement that popular game engine maker Unity will be supporting WebGL as a target for 2D and 3D games developed using its IDE:
http://blogs.unity3d.com/2014/04/29/on-the-future-of-web-publishing-in-unity/
Here is an example of a game built in Unity and published to WebGL:
http://beta.unity3d.com/jonas/DT2/
(Don't forget to press escape at the start to dismiss modal message. Otherwise you'll die. Currently supported browsers for this content are Firefox and Chrome 35)
Biting the hand that feeds IT
