From the Microsoft Patterns and Practices Team comes the Web Client Software Client Factory June 2007 Release.
WCSF makes use of Guidance Automation, Application Bocks and Libraries.
It makes developing a composite Web Application much easier and automates several (otherwise laborious) processes whilst also offering advice and guidance on various topics.
I have found it makes implementing the Model View Presenter pattern very quick and easy.
Its also worth a look if you want to get into developing Page Flows using Windows Workflow Foundation.
You can read more and download it from the official web site.