There are some very good wireless video sending/receiving units that will send a video signal wirelessly through walls and such. They don't send antenna signals, just video signals. I have used them with good success.
If you're going to run RG6 throughout your home, do yourself a favor and run TWO RG6 cables and two CAT5 computer cables to each location from a single location in your house (sometimes referred to as a head end). You can then use the RG6 cables for and in and an out and use the computer cables for computer or telephone (yes, some folks still have wired phones).
For example, in our house, we have both a dish and an antenna mounted on the garage. I feed the antenna and dish into a diplexer and combine the signals onto one coax to our head end combiner in the basement. I then feed to our living room from the head end combiner over one coax. In the living room, I have another diplexer and seperate the dish and antenna signals to feed the dish box and digital converter box. I send the output of the dish back out of the living room over channel 3 back to the combiner at the head end. That way, I can put any other TV in the house on channel 3 and watch what is on the dish. I do the same thing for the DVD/VCR on channel 4. The TV in the living room is the only one that has HD, so I do not notice any display issues in the bedroom, laundry or garage. Also, I can put the dish on one of the music channels and listen to stereo music on all of the TVs in the house. There's lots you can do. Just do some research before your start poking holes in your walls. :laughing: