SCENE: Sheldon is walking backwards along a corridor,
against the flow of people coming the other way.
He is prominently holding an HP calculator in
front of him in one hand, whilst entering numbers
with the other. People are constantly bumping
into him as they try to avoid him.
SHELDON: (as each person bumps into him)
I'm sorry.
I'm sorry.
I'm sorry.
Leonard sees this from the start of the corridor and
pushes through the on-coming people to catch-up with
Sheldon.
LEONARD: (exasperatedly) Sheldon! What are you doing?
SHELDON: I'm using my calculator, of course.
LEONARD: (patiently) Yes, I *know* you're using your
calculator. Why are you walking backwards
along the corridor?
SHELDON: (condescendingly) Isn't it obvious, Leonard?
It's an HP-41 which uses reverse Polish notation.
Ergo I should be going in reverse when using it.
LEONARD: Isn't that just taking things a little too far?
Why can't you use it but walk forwards?
SHELDON: But then it would be just Polish notation and
the answers would be wrong.