Seems similar in concept to a sling box.
www.slingmedia.com
However, Orb sounds heaps better in relation to a MCE PC as a sling box takes an AV input and broadcasts it.
Have you ever tried PCAnywhere, VNC, RemoteDesktop for this sort of stuff?
I tried using RemoteDesktop as an extender solution. Very little success with video though... Now have an XBox360 ; Micro$oft...