Came here to mention this. I saw one around 1985: our numerical methods professor had one but we did our homework on a DEC-20 with a "proper" LA36 terminal with APL font and keycaps.
Wonderful course, taught in APL from the Red Book. Every example and homework was a one-liner. This is why a machine with a one-line LED display was even feasible in practice. And those little cassette tapes probably held a ton of programs.