The Lemokey L5 HE 8K is a mechanical keyboard aimed at gamers that uses magnetic switches. This results in a keyboard that is ...

work quite differently — they use a permanent magnet in the switch stem to change the magnetic field when the key is pressed.

Waveguides come to mind, but so do active elements like filters made from nothing but PCB traces, which is the subject of this interesting video by [FesZ]. Of course, it’s not quite that simple.