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@futurebird YEAH!! YEAH!! THIS IS RADICAL!! There's literally nothing that says we can't put algebraic numbers on a ruler!! 
Slide rules already do this with e and pi and conversion factors to/from arcminutes and arcseconds!
What I'd love to see is a "complex ruler". A combination ruler and protractor that can "measure" a complex number in its polar form (slightly more advanced than studying them in cartesian form, but makes them A LOT easier to conceive as actual numbers imho)
@futurebird My electronicsy butt and operational amplifiers.
They were triangular black boxes in circuits until I understood their parsimonious equation: Vout = Vin+ - Vin-
This came after watching a video that broke them down into a few simple properties. The equations that describe different op amp configurations are merely derivations of the original after a bit of analysis of the surrounding feedback loop(s).
It is now circuit analysis a la kirchhoff that eludes me a bit.