I have always been fascinated by the concept of Federated Identity and the need for SSO across domains (not just intra-company but also inter-company, inter-partners). The specification that brought this into the forefront is the Oasis SAML specification.
I have been elected (basically with unanimous consent) as a secretary of the Oasis Security Services Technical Committee (SSTC) which is the driver behind the SAML specifications.
Take a look here: Oasis SSTC Home Page.
Still learning to be a secretary of a prominent specification body. :)