No - this is not about computers - it's concerning my memory.
I'm usually pretty good at remembering things that happened years ago (Even though I often
fail when it's something only minutes ago). But here's my problem:-
Many years ago I used to have a projector, that I used when giving lectures, which did not
take photographic plates or slides, but in which you could insert any piece of paper or illustration.
I can't for the life of me remember what it was called. Any ideas?