Scott Guthrie announced a CTP release for ASP.Net Extensions available for public download. Lots of exciting features that you can play with, including the new ASP.Net MVC Framework, as well as the Entity Framework.
ASP.Net 3.5 Extensions CTP
MVC Toolkit Extras
Also download the beta 3 build of Entity Framework Tools for Visual Studio 2008 RTM from here.
ADO.Net Entity Framework Tools Dec 07 Community Technology Preview