I am currently re engineering the portal starter kit
-> layering (data\business\facade\framework)
-> multiple databases support
-> web services layer
-> windows client for admins
-> .NET 2.0 \ .NET 3.5
take a look www.codeplex.com\aspnetportal
I like the portal starter kit because it's simple; I have used it in the past to kick off many web apps. Now it's time to get it up to date.