If you replace your standard home thermostat you find the most common setup has either 4 or 5 wires ... is a Raspberry Pi 3 B+, booted over PXE, with the official 7 inch touchscreen, mounted ...

[Andrei Istodorescu] has been hard at work building a 7″ touch-screen rig which runs XBMC. It may be upside-down, but the Raspberry Pi board which is front and center is still easily recognizable.