There's a multitude of options. Apple TV (too restrictive), Roku or Boxee boxes (bit expensive for my likings), numerous HDMI docking stations, WD TV I have a 1TB esata drive that I'd like to use for playback rather than going the wireless route, although would consider wireless. Any suggestions around the $100 mark?

I heard that it is already running a linux under the hood. So that would mean it is possible to install others such as xmbc, right? Anybody know how?