I just set up MythTV to stream video from the desktop to my laptop. I’ve had to muck about with the playback resolution because the poor little laptop just doesn’t have the hamsters to playback HDTV at full resolution. It’s also running over 100MiB wired ethernet, not GigE. It’s quite watchable. I’ll be interested to see how well it goes over the wireless LAN connected up to the TV. I suspect I’ll end up having to use either a dedicated server or a super long SVGA cable and IR repeater the way Bevan is.
Regardless, free software rocks.