After listening to Garrett's (and friends) presentation at MIX07 on CardSpace, my eyes were opened to the new wave of business opportunities that the identity metasystem will give.
The presentation cited a new Canadian business that are using managed cards providing claims that captured in formation about people's body sizes.
Users can use these managed cards to sign in to sites selling clothes, and then they would can be directed to clothes that fit their body shape. Also, the users can use models to visualise what the clothes would look like when worn.
This is a very simple example of how claims based systems can create new businesses and enhance the offering of existing businesses to the consumer.