I have my house wired so that every television can access a shared set of sources (mostly). I wanted this solution because everything I watch is recorded. Therefore, I wanted to access each of my three DVRs on every television in the house. Here is how I accomplished it.
First, I located all of the DVRs in the basement. They are each run to every television in the house using different transmission mechanisms. Here is a general overview of my system layout:
The Basement and Family Room are in close proximity, allowing direct wiring of all the devices. The DVRs are wired directly to the TV using Component and S-Video connections. The sound is sent back to the basement from the DVD and game consoles using digital audio connections. The speakers are wired directly from the AV Receiver in the basement.
The rest of the rooms require some alternative transmission mechanism. For the Standard Definition (SD) televisions, I use a Channel Vision E4200 RF converter. This devices takes up to 4 standard definition sources (audio and video) and modulates them onto broadcast channels. I then combine the Antenna feed with the Channel Vision output and run it on the RG-6 that runs to each television in the house. Now ever TV can tune to a channel, say 63, and display the output from the SD DirecTV DVR. I also have a Cat-5 run to each television with an IR Sensor. This allows signals from that room to be transmitted back to the basement and be 'seen' by the components there.
For the second HD TV, I use a system from Audio Authority (Model 9871 + Wall Plates) to transmit a High Def (HD) component video signal, digital audio signal, and IR signal to the second room. This system requires a converter box at the source and destination, but allows all of the signals to travel over a pair of Cat-5 cables.
Here is an overview of the wiring:
The Audio Authority system is great for transmitting HD video, as long as it is component and not HDMI. See my rant against HDMI for more information.
I use a Niles IR system to capture/repeat the IR signals. It has worked well, although there does appear to be a quality difference in the IR sensors. Spend the money to get a good one.
For music I use my laptop to stream music to one of two Airport Express devices, attached to each AV Receiver in the house. It isn't a Sonos, but it works.
I have a Harmony remote in each room setup to control the local TV and the DVRs.
Overall, I've been very happy with this setup. It has been in place for over three years now and just works. There are certainly other solutions to this problem, but I've been pleased with this for my needs.