(aka Xbox Meda Player, which is the pre-1.0 release of XBMC)
http://www.xboxmediacenter.de/
XboxMediaCenter (XBMC) is a multimedia player jukebox for Microsoft Xbox game console, it is capable of playing back almost all known video, audio and picture formats from the Xbox harddrive, Xbox DVD-ROM, from a local network or even from Internet.
XboxMediaCenter uses mplayer? as it's primary media player, which is a linux port for the windows 2000 kernel that runs on the Xbox.
More information, screenshots and videos soon.
One page links to XboxMediaCenter:
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