A Browser MMO using Three.js, Socket.io, and Node.
The entire game is built using Coffeescript for that much needed syntatic sugar and readability. Using Backbone for the frontend framework simplified syncing with the backend, and a bunch of other things like event binding etc... I could also share the same models and collections with the Node backend.
Brunch provided an amazing build pipeline, automatically compiling and optimizing the entire application for deployment. Socket.io provided realtime communication with the backend via HTML5 Websockets.