A great guide has been created on ProductWiki – How to mod your Xbox and install XBMC. The media playing capabilities of XBMC have to be seen to be believed – I really struggle to think of a better media playing device (at this moment in time). Well worth doing if your thinking of buying some sort of media playing device that would sit near your TV. Further info can be found at the XBMC Homepage or on the forums at Xbox-Scene.