I'm lookin to rack mount and cluster a few cabinets full of RPi3s together and powering them through the GPIO ports and loggin into them via WiFi. This means I wouldn't need to have no stinkin wires. I like to do what this youtuber did but I want to do something a lot bigger.
My biggest expectation is that over time that I would have RPi3 failures or would need to upgrade a lot of them at once and just want to yank the bad one out (either blink all the LEDs and find the one that isn't blinking, or if I do have connectivity, just blink the faulty system) and hot plug in a new one without having to bring down any other systems in the grid. (it might even be a RPi4 by that time.)
The youtuber didn't have the luxury of WiFi so he had to use network cables, but he did power the boards through the GPIO ports which I like.
I want to take it another step and hot plug Pi3s into a backplane or make a rigid 90 degree 40 pin GPIO to PCI-e adapter and plug them into PCIe slots to get power (This could be dual purposed for either small scale into existing desktops or a large scale PCIe backplane for power). I don't see anything like this, so it might be a nice fritzing project. Before I wasted a lot of time on this project researching the feasibility of this, I just wanted to see if there might be something out there already to jump start me.