rQRCode, a Ruby library for encoding QR Codes
[Update]: I have also posted a bit more about the upcoming QR Code work for BBC /programmes.
Since then, I have done lots more research and think there is great mileage there for promotional material and advertising. At the moment the codes are built on the client side, but this will be moved to the server soon so we can start caching the pages, and also so we can provide the code in a more useful format (maybe images instead of the current HTML table).
You can find out more over at it’s project page on Github:
So that should get you going. Enjoy!