I have been using a multiplexer to put the output from my Dish receivers onto different channels, mixing that with my OTA antenna, mixing in a VCR output for good measure, and then sending that back out throughout the house. This lets me watch anything on any channel at any location in the house. I currently have 4 remotes, 2 for each of my 522s (which I recently acquired). I switched the 522s to single mode, and that works well since we currently only use 2 channels at once at most. If I ever had contention, I could switch back to having 4 channels of Dish pretty easily.
I can only add four inputs to the data stream now. I had been using a TriplePlay Modulator (3 inputs) for years, but it finally died and I replaced it with a ChannelPlus box that allows for 4 channels.
Brad