I don't remember much but I see there are many articles from people who've hooked a Minitel up to a Raspberry Pi or similar in recent times. I think it had a non-standard DIN connector, and you could make up a special cable to get RS232, possibly with a voltage change, not sure about that, and then I think you just had to talk to it very slowly; maybe 1200/75 baud, something like that. There were terminfo definitions for minitel (various models) and I see they are still there in Debian, which means you can write programs using libcurses to do primitive, slow 80s style user interfaces!
If I had space in my life for more retro-junk I'd definitely love to have a working DEC VT100 or Lear Siegler ADM-3A if I could find one with the tube in good sharp condition so you could actually really use it to hack code on... but they probably go for a fortune by now, and ... well I just don't have space. For a slightly less rare and valuable terminal, a Wyse 60 would also be a good option (unless I'm misremembering, the keyboards were very nice and you could absolutely work on one of those today). When I was a kid all the libraries had Wyse 60s as catalogue search terminals, and I also learned how to use Unix through one of those beautiful things.
I had a couple of Wyse 60s that looked basically new when I got them, and they both broke (refused to display anything) quickly. It is rare in general for computer equipment to break when in my possession.
