ContributorNetwork - The Humble Indie Bundle is a promotion that started in May 2010 and has reappeared several times since then. It's a collection of games from indie developers, that's sold as a download with no DRM (meaning you can copy it as much as you want). What sets it apart is that you can name your own price, or even donate the money to charity instead. And all of the games are cross-platform, meaning they work on Windows, Mac OS X, and Linux.
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