I remember a guy I know went to japan/asia around 1985ish and came back with a watch. It had hands, but also a small LCD display. You could draw numbers on the face with your finger, like 6 then X then 3 then = and the LCD would show the values, and finally 18
This is completely uninteresting now, but this was 40 years ago
It was a really interesting and weird time growing up when Japan was the king of tech. I had a friend who's dad was often over there and bringing all sorts of weird stuff back. There was this NES/Famicon game where you played with a sort of gyroscope. I have no idea how you were supposed to play the game, but found the gyroscope endlessly fascinating. Then of course there were the pirated cartridges with 100 in 1 type games. Oh then we found the box full of his dad's "special" games. Ah, good times.
There were some licensed games in Japan that they'd never release in the West, and also a relatively large scene for unlicensed/'bootleg' games. Fun slightly related factoid - the Game Genie was an unlicensed hardware mod and they actually got sued by Nintendo, and won.
I somehow suspect in modern times they'd have lost.
This is completely uninteresting now, but this was 40 years ago
EDIT: I think Casio AT-552
https://www.youtube.com/watch?v=0aQHnyZdgF4