Unusual part applications

[amyk]

I came across this article on an incandescent bulb in HV circuit of CRT monitor:

http://www.righto.com/2017/10/inside-vintage-xerox-altos-display-tiny.html

Does anyone have other interesting stories of parts used in unusual ways? I once came across a piece of network equipment which would emit beep codes if something was wrong --- but when I opened it up to troubleshoot, there was no sign of any piezo speakers (that's what it sounded like); the beep codes were coming from a large bank of ceramic decoupling caps, and the processor was programmed to draw current at precisely the right frequency to make them beep.

[sleemanj]