I am captivated by the work going on in the identity space and as a result have created a collection of resources that I particularly like. If you are interested in this space too and want to know where to go for information, consider these resources.
Zermatt Developer Identity Framework
Microsoft Code Name "Zermatt" white paper for developers
Digital Identity for .NET Applications: A Technology Overview
The Architecture Journal #16: Identity and Access
MSDN WebCast: Overview of Developer Identity Framework (Zermatt), 9/26/08
Vittorio Bertocci and Caleb Baker: Understanding CardSpace and the Complexities of Identity
Demystified Series: Active Directory Federation Services (AD FS) Part 1
Demystified Series: Active Directory Federation Services (AD FS) Part 2
Understanding Windows CardSpace: An Introduction to the Concepts and Challenges of Digital Identities
Kim Cameron's Identity Blog
Vittorio Bertocci
Don Schmidt
Mike Jones
Identity Metasystem
Microsoft Identity Lab