[jbbmhwpt] Modern abacus

The modern abacus provides primitive operations comparable to a CPU, and, most importantly, a physical interface with which the operator can very rapidly perform sequences of operations (algorithms in the lingo of cubers), distinguishing it from a mere desk calculator.

Registers, stacks, RAMs.

Add, and, or, not, xor, shift, conditional execution in the style of ARM instruction set. Perhaps omit multiplication to provide the pleasure of executing an algorithm.