Polymer, a Web Components library built by Google
I was at the Google IO talk and talked to Matt McNulty, my old boss from Palm, and was blown away with what they're building.<p>This is the future of UI in the browser.<p>The declarative nature, the encapsulation, the data bindings, the attribute and event-driven APIs are all orders of magnitude simpler than existing JavaScript / HTML UI element componentization. The reusability of a custom element compared to an HTML snippet with some associated JavaScript and CSS cannot be overstated.<p>EDIT: understated > overstated