Scott Guthire write in his blog about new release of ASP.NET AJAX Control Toolkit and Web Deployment Project for Visual Studio 2008. ASP.NET AJAX Control Toolkit is free for download and contains additional AJAX controls and components. Web Deployment projects can be used with either the "Web Site" or "Web Application Project" options built-into VS 2008, and provide a few additional build, packaging and deployment options for you to use. Check this out here.
Visit his post here: http://weblogs.asp.net/scottgu/archive/2007/12/01/asp-net-ajax-control-toolkit-and-web-deployment-project-releases-for-vs-2008.aspx;