This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
The application expires every two weeks and you will need to download it again.
I'm not sure about the license, the source code isn't available AFAIK. It is free now but I guess it is going to be a commercial product in the future.