Real-time synchronous multiplayer 3D gaming with HTML5

The game itself is here: http://airhockey.artillerygames.com/

How long did it take to build, and which part was most difficult?

Most of the work was done inside of a week with no plans to ever launch it publicly. Then we changed our mind, spent another week on it and wrote up a blog post.

The hardest part was probably the mutliplayer networking and latency compensation. It required a lot of tweaking and it's still far from perfect, but I think it's pretty reasonable for two weeks of work :)

hard to believe it's html5/javascript