This is just a taster. This is an interesting edge-lit numeric display from the 1960s, a successor to the Nixie tubes. The arrival of 7-segment displays in the late 60s probably made these ones obsolete so they are quite rare.
Each digit 0-9 is inscribed on a thin piece of transparent acrylic and these are sandwiched together. Each digit can be illuminated by its own 28-volt bulb.
Nowadays bright white LEDs are the alternative to small bulbs so here we have the digit '8' being lit up by an LED driven from 5 volts.
More to follow.