🚀 go-pugleaf

Okay, this isn't computer folklore any more, but I don't know where
to redirect followups...

Greg Goss (a80@mindlink) pointed out in article <3528@mindlink.UUCP>:
>C is CENT and M is MILLE.  D might be demimille.  I dunno about L.

[Throughout, the symbol @ represents an upside-down capital C,
and   I@   represents a capital I followed by an @. Note that it
looks much like a D.]

My dictionary gives     I@   as an alternative symbol for D.
Indeed, it even gives  CI@   as an alternative way to write 1000.

Can any historians explain the background of this notation?

ObFolklore: Sending harmless cursor repositioning commands to somebody
else's terminal (e.g., save cursor, repeat n times: [cursor up, cursor
down, cursor left, cursor right, cursor right, cursor left, cursor
down, cursor up], restore cursor; for moderate sized values of n) and
watching him bang his terminal to fix the loose connection.