The Humble Indie Bundle was a huge success, making over 1.25 Million Dollars for the game developers and the charities. This has been a great example of what can be accomplished with the "Pay what you want" model, and a huge success for Linux Gaming, as well as DRM-free gaming. As part of the promised outcome of this huge success was that 4 of the 5 games would be open sourced. As of today, 3 of the 4 have been released. This isn't the complete success I was hoping for, but it definitely meets my expectations. The reason it wasn't a complete success was because although they have released the source code sufficient for users to build the games, they are maintaining control of all of the arts and assets. I see their perspective, being able to retain control of the creative side and the trademark, while sharing the logic and code with the world.
Gish can be downloaded or forked from Github at http://github.com/blinry/gish.
Penumbra can be downloaded or forked from Github at http://github.com/FrictionalGames. It is split into 3 different projects for the different modules the game is built into.
Although this project is being hosted and maintained on Icculus.org, there is a Github copy at http://github.com/pvtcupcakes/Lugaru being maintained by volunteers.