My thought exactly. Make voice recordings and randomly broadcast ghostly screams into the elevators. Not something I would do, but definitely a DEFCON prank waiting to happen.
"Attention customers, due to signal delays, this elevator is now running on the express line. For local service, please transfer to the 1 train at the 168th street station."
``Hello,'' said the elevator sweetly, ``I am to be your elevator for this trip to the floor of your choice. I have been designed by the Sirius Cybernetics Corporation to take you, the visitor to the Hitch Hiker's Guide to the Galaxy, into these their offices. If you enjoy your ride, which will be swift and pleasurable, then you may care to experience some of the other elevators which have recently been installed in the offices of the Galactic tax department, Boobiloo Baby Foods and the Sirian State Mental Hospital, where many ex-Sirius Cybernetics Corporation executives will be delighted to welcome your visits, sympathy, and happy tales of the outside world.''
``Yeah,'' said Zaphod, stepping into it, ``what else do you do besides talk?''
``I go up,'' said the elevator, ``or down.''
``Good,'' said Zaphod, ``We're going up.''
``Or down,'' the elevator reminded him.
``Yeah, OK, up please.''
There was a moment of silence.
``Down's very nice,'' suggested the elevator hopefully.
``Oh yeah?''
``Super.''
``Good,'' said Zaphod, ``Now will you take us up?''
``May I ask you,'' inquired the elevator in its sweetest, most reasonable voice, ``if you've considered all the possibilities that down might offer you?''
