I disagree with an earlier assessment that the XBOX modding is not easy. I knew absolutly nothing on the topic and in a matter of days (these great tutorials!) I had my mod up and running.
I was running a similar setup at my house. A wireless laptop S-video'd into my TV to run my emulators and stream info from my server.
Let me tell you... that setup does not compare one iota to this XBOX setup. This one, conspicuous box now performs the task of several machines. It runs all the emulators perfectly and the streaming quality is tremendously superb. The first time I ran XBMC and heard my mp3's playing back in DTS digital surround through my XBOX I was blown away.
The combination of the emulators, the streaming audio, video, pictures, etc, the DVD player (with great original features like true zoom and pan), and the games makes this little endevour the most satisfying I have had in a long time