a friend of mine actually took that idea a step further...
his bedroom shared a wet wall (wall with plumbing) with the bathroom, and he cut a hole into the wall, spliced a t-fitting into the cold water pipe, and ran the pipe into the back of his stand directly into a R/O with pressure regulator.
last time i talked to him he was trying to set it up to automatically top off, and pondering how to hook into the drains from his room...