Quickly prototype electronics by hand-milling copper-clad PCB

All you need is a magic marker, a copper-clad PCB, and something like a dremel. Isolate nodes by hand, then solder components onto the PCB. I'm probably not the first to come up with this, but I hadn't seen it before.
Advantages: easier to decypher / debug than a typical veroboard setup, everything on 1 side, isolation-distances as big as you want, components are drawin on the PCB, able to use components that don't fit into a veroboard/breadboard, and able to make low-impedance tracks where you need them.
(I made an overly looooooong video about different electronic prototyping methods earlier, but this method was not included yet. I will use it in practice now, to prototype a switchmode PSU.)