SparkyLinux is a Debian-based Linux distribution which provides ready to use, out of the box operating system with a set of slightly customized lightweight desktops.
ChimeraOS (formerly GamerOS) is an operating system that provides an out of the box couch gaming experience. After installation, boot directly into Steam Big Picture and start playing your favorite games.
Game Drift Linux is a new Linux distribution based on Ubuntu Linux. Game Drift has been optimized to deliver to you the best possible gaming experience on Linux.
The distro is no longer updated. Last version, released in September 2011, can be still downloaded from the official website.