Today's Deal of the Day from O'Reilly at
http://shop.oreilly.com/product/9780735627185.do is "Programming Windows® Identity Foundation"
"Get hands-on guidance designed to help you put the newest .NET Framework
component- Windows Identity Foundation, the identity and access logic
for all on-premises and cloud development- to work.".
I have reviewed this book previously at
http://geekswithblogs.net/TATWORTH/archive/2010/12/24/programming-windows-identity-foundation---isbn-978-0-7356-2718-5.aspx. It is a book I recommend to all Dot Net Development teams.