Web user interfaces can do a whole lot more today than they could a year or two ago. Some of these changes require rethinking how things are done on both the client and the server. In this talk, I'll focus on using TurboGears 2 and other Python-based tools to make a server side web API that works with a “smart” browser-based client (built with Dojo), vs. the more traditional “dumb” client model. I'll also explore how you can use TurboGears 2 to create Comet applications which allow the server to communicate back to the browser as needed. Note that this talk includes a lot of JavaScript, because it's all about moving more of the presentation over to the client.