I have done this (and still do) with all my plasmas mounted on walls. I use a tilting wall mount bracket from Monoprice, and just rest the back end of the cable box on the main part of the bracket (that is flush to the wall), and the front part of the box rests on the back of the plasma. IR signals easily reflect from the ceiling so the remote works well. You just need to remember to point the remote above the TV instead of at it. In fact, behind my main floor wall mounted flat panel, I have a cable box, a router, a Western Digital TV Live streamer and a portable hard drive, all tucked neatly behind the TV.