Netflix gets a non-exclusive license from the winner, so they can sell it to other parties, and it seems like something that various parties would be willing to pay for.

An open source version would be a significant act of charity. It would be nice to see older versions or versions that were crippled enough to be education without watering down the reward that the winnners receive.

Algorithms have already been published for the Progress Prizes for 2007 and 2008.

Open sources projects have already been created in Python, Java, C, and C++. None of these projects include the full algorithms from the 2007 or 2008 papers.

The projects can be found from links on the Netflixprize forum:

http://netflixprize.com