New in the top floor:

• ATX power supply
• multi socket
• powered USB hub
• junction box (supplies power to ATX PSU, multi socket and scope)

PSU is not really connected yet (apart from mains). Here's the multi socket:

It has 3 outlets, two if which are used for the RPI's and USB hub's wall warts. The hub is installed towards the side because that was simply the easiest thing to do without having it stick out from the front. Yes, the picture quality sucks, but it does the job: