Peer to Peer networks are very popular these days, though most of them have very shady and not-quite-legal intentions. One legal P2P network that will be debuting soon comes to us from NDS that creates PVRs for DirecTV. A PVR with it's own P2P network, I like the sound of that.
The first thing you have to look at is their new “Distributed DVR” which essentially lets you share the content stored on the PVR with any of the PC's on your home network. Now that by itself is enough to make me want one. But here's the kicker, they're going to introduce ShareTV, a P2P network that allows subscribers to view and download content from any other ShareTV user. And from there you can transfer it to your PC. Theoretically, this would enable users access to content from channels to which they do not currently subscribe. (I'll pause to let you get your minds out of the gutter) I'm not sure how this will make the MPAA feel, but if they can get all of the legal issues, I think this will revolutionize the PVR market.