I used one of these in high school, calculating asteroid orbits. Does anyone remember the "FoCal" language, sort of a combination of Fortran and Basic?
Later, in college, I worked one summer with an Intersil system that emulated the PDP-8, which was, I believe, the first microprocessor system. This was going to be used to control the seismic stations in Southern California, so that they could store quake data on site for later retrieval and analysis, rather than sending it in real-time via phone lines, which is problematic during an actual quake.
Knobs, buttons, blinking lights, paper tape; those were REAL computers back then.