This is a great alternative to RCP wiring! It looks like it would save a LOT of tedious work and time. But how do the pins retain their connection to the board if it is being bent almost completely?
It works because the copper cladding traces are etched from is malleable, and because most of the traces going to the cart slot are on one side of the board.
In theory, this could be done to any single sided circuit board.
When you slice through the backside of the board, you remove the rigid surface that the traces are adhered too. Once this is gone, you have effectively turned the traces into very short, very fragile wires. From here, you can carefully adjust the angle along the single degree of freedom you have given this part of the board to your liking, but you must be very careful with it, because the wires are so thin. After that, epoxy it in place, and you have the equivalent of two circuit boards assembled at an angle to each other. Since this was one board, and we want to feel more awesome, we refer to it as board bending.
Where the board is two sided, you need to rewire the traces you had to cut for the bend.
I've never actually bent a board, but I think the best way to get a perfect bend would be to use a triangle file. Goes slow, makes a straight, nice and even cut; would make it harder to screw up a board and you'd get a nicer fold IMO.
I just use a dremel with a cutting wheel. Score a very light straight line , then cut along the line till you see white dust. It is a tad harder to bend but a lot less chance of cutting through.