I love Escape from Butcher Bay. The Xbox version has an extra level apparently, called Assault on Dark Athena. That version of the game is named that too.
Actually, Assault on Dark Athena is mostly a remake of the game for the next gen consoles with extra stuff. The PC version had an extra level over the original XBOX one, but the 360 and PS3 thing is going to have even more.
edit: or were you talking about the upcoming 360 version? I just assumed you meant the original xbox.