I've just read all those links and quite a few from them. I now understand rather more than I did.

And the whole family of those devices still scares me. I am more at home with a slipstick and I barely know how to do the simplest things with one of those. I have always felt, and still do, that RPN goes against the gods and nature. If man were meant to think that way, we'd have, erm, a word for "enter" or something, in, erm, English. Or something.

Um. I'm going for a lie down now.