A proof-of-concept for using Passbook
You can see it here:
http://shrouded-plateau-7574.herokuapp.com/ | git@heroku.com:shrouded-plateau-7574.git
Beginning Passbook in iOS 6: Part 1/2
http://www.raywenderlich.com/20734/beginning-passbook-part-1
Supporting Passbook within Your Enterprise Systems
Passbook rails example app
https://github.com/mattt/passbook_rails_example
Sample Passes
https://developer.apple.com/downloads/index.action?name=Passbook%20Seed%20Support%20Materials