ARSCIF is a powerful framework that makes it trivial to use asynchronous remote-script callback invocation (AJAX) techniques. It helps the developer by working out problems such as data and character encoding, concurrency control, browser implementations, and so on, allowing the creation of pages with sophisticated, dynamic features.
Abmash provides Web application automation based on visible rendered output. It is all about interacting with a browser as humans would do, including AJAX and forms. It lets you perform tasks like "Click the red button", "Give me all text elements directly below an image", or "Click 'Login' and wait until the login form is loaded, then type in my credentials and submit the form".
Address Book Continued is a multi-user address book Web application. It also makes use of AJAX, which means that page reloads only happen on login/logout; the rest of the operations is handled asynchronously in the background. It's well usable, even over slow connections. You can even install ABC on your desktop PC and configure it so that it doesn't require login for connections coming from the local computer.
Brockman is an information radiator for monitoring Ant builds. It is useful for Agile software teams that practice continuous integration. Brockman consists of an Ant listener written in Java that outputs that status of your build in XML, a Freemarker template that specifies the format of the output XML file, and an AJAX front end that renders the XML file.