Back in the olden days, "multimedia" meant two slide projectors, a dissolve unit (so one image would "dissolve" into the next) and synchronized sound track. But back in 1984 there weren't any dissolve controllers that met my needs, so I did what any self-respecting engineer would do - I designed and built my own circuitry, and programmed my HP-71 calculator (MUCH more powerful than the HP-41 previously mentioned!) in assembly language just to put on a show that moved people emotionally (like this one: https://friedmanarchives.com/peace-child-in-lativia/ ).
