Want to send an HDMI signal a long distance through your house without signal degradation?
HDMI Over Fiber Optic
Rainbow Fish has an answer for getting an HDMI signal over long runs in your house: They send it via fiber optic cable! It will allow 1000 foot runs.
Coming to the Consumer Level
This isn't just a professional installer solution, either. A consumer-targeted version of the optic cable is headed your way very soon.