The only reason why I own an iPod touch is the App Store which has an incredible amount of free (and commercial) games and applications. Sometimes I wish that the package manager of my linux distribution would be as easy to use as the Apple App Store. I know that there are many nice games running on linux, the only problem is to find those games.
The solution is the Game Store created by Pavol Rusnak. Finding a game, installing and starting it is just a matter of three mouse clicks. All listed games are not only free, but also open source. Playing games on linux is finally easy and fun!