Mach 1 Slide Rulette - made in 1972, one of my older ones. Has a really nice glowing green VFD, vacuum fluorescent display. Obviously very well made.
Sears M8 - made in 1973 by Sears, came in a nice black leather carrying case. The side of the calculator has an orange stripe down it, which makes the whole thing look gorgeous.
Sharp EL-827 - made in 1981, my #1 favorite, a musical calculator. It's fairly quiet, but you can hear it in a quiet room easily. The keys each have different notes for them, so you can play songs on it. I've learned a handful of songs on it myself. A really tiny, little, gorgeous thing - slimline, brushed metal, super thin. Just beautiful.
Sure. Musical calculators were initially made for the blind (so when you press a key, you hear a sound and can tell what's happening.) When you press equals, for example, the calculation happens and the calculator sounds out the tones for the answer - for example, you enter 9x9=81, and you get (9 tone) (multiply tone) (9 tone) (equals tone) and then the calculator sounds out (eight tone) (one tone).
Eventually people started using them as toys or musical instruments, so some calculator companies started making the sounds less robotic and more musical - and now there are "musical calculators".
