“Zermatt” is the codename of a .NET framework that helps developers build claims-aware applications to address challenging application security requirements using a simplified application access model. It is currently in beta, and the first final version is expected towards the end of this year. This framework consists of a comprehensive set of libraries that facilitate the use of "claims" in applications - in Microsoft's words: make them "claims-aware". This greatly simplifies the development of applications that will work within federated environments and the new identity metasystem technology that Microsoft is developing, and will give a push to adoption of the new identity technology.
Download the bits of the Beta of “Zermatt” Developer Identity Framework.