I was in Walmart looking through the clearance area and came across the Sanus and Power Bridge in wall wiring kits for a wall mounted HDTV. I have used two Power Bridge kits in the past and they are great DIY kits to wire up a wall mounted HDTV and hide the cables in the wall for your external devices.
These are YMMV and I'm sure there will be people who thumb down the deal because of that but I was able to get 3 of each kit from two local Walmart's. My sister and I have new houses being built so 3 were for her and 3 were for me.
Power Bridge: as low as $13: https://brickseek.com/walmart-inv...=300625308
Sanus: as low as $1 but most are $9: https://brickseek.com/walmart-inv...=592118513