The HP-41 was fascinating for an obscure reason called "synthetic programming". It was a series of key presses and operations that unlocked a mode in the calcul

The HP-41 was fascinating for an obscure reason called "synthetic programming". It was a series of key presses and operations that unlocked a mode in the calculators that allowed you to do all kinds of things that were never allowed in the first place, such as controlling individual pixels on the screen. It was absolutely magical http://www.hpmuseum.org/prog/synth41.htm http://www.hpmuseum.org/prog/synth41.htm