Google's Build With Chrome app, which lets you construct LEGO structures online via a WebGL app, has been available in Australia since mid-2012. The big G has finally decided the app can be available to the rest of the world, and has also beefed it up with new tutorial and exploration modes.
There are also new categorisation options, and the ability to share your creations with Google+. (No, Google hasn't given up on that one yet. It's hard to argue with a way of building Lego that eliminates the risk of treading on one of the bricks, but be warned: this can suck up a lot of your time.
Chrome + LEGO: You can build whatever you like [Official Google Blog]