On my webcast today, I received many requests today for additional information on ASP.NET 2.0 Membership and Personalization articles and tutorials.
Dino Esposito's article, Personalization and User Profiles in ASP.NET 2.0
Writing a Custom Membership Provider
Passport Authentication Provider
From the Patterns & Practices Team, Security Guidelines: ASP.NET 2.0
Detecting if a client's browser supports cookies
And of course, there's always http://beta.asp.net.