Atlas ASP.NET
Atlas is Microsoft's framework for AJAX-style web application development. The recently launched Atlas site provides developers with software, documentation, quick starts, and hands-on exercises. ASP.NET Atlas is a package of Web development technologies that integrates an extensive set of client script libraries with the rich, server-based development platform of ASP.NET 2.0.Atlas enables you to develop Web applications that can update data on a Web page by making direct calls to a Web server — without needing to round trip the page. Visit the Atlas Community Preview Site.