XBMC (XBMP really) started as a program for modified XBOX consoles. In the following years, XBMC has grown into a multi-platform, multi-architecture media center that runs on most standard hardware. The hardware and legal limitations of the XBOX were always a concern and the Team has instead focused on running on the hardware that most people already have.
I once owned an xbox that had been softmodded to use XBMC, and it was the best thing since sliced bread. Then lightening hit it, and I ended up buying an xbox 360, and everything was ok with the world again. Now, I’m using a dell mini to play all my streaming files, it has hulu, xbmc and wmc on it.
via Farewell XBOX | XBMC.