Google released Chrome 58 Canary this week, which enbales WebAssembly by default. The action gives Chrome more power to run Web apps directly in the browser, but this is early days.
This browser preview available in Chrome is janky at best. Canary-branded builds from Google are essentially in alpha status and won't be finalized for some time.
If you're interested in taking a look at what WebAssembly can do, Google is providing a neat peek via this demo. In order to view the demo, you have to first download and install Chrome 58 Canary. Versions are available for MacOS X 10.9 or later, Win 32, Win 64, and Android.