Here are a couple of clippings from “A Brief History of Optical Synthesis” by Derek Holzer:
A flame-based spectrum analyser - no moving parts:
Patching analogue data:
Iannis Xenakis presents an all-drawn music composition system:
This slide deck is one of many interesting contributions to Devine Lu Linvega’s request for examples of “anything relevant to paper computing”.
We also find a link to this, which I’m sure @Maurici_Carbo previously brought to my attention:
Devine’s website also has much of interest: