The Devil Car (MWEB)

Murdock and his sentient car, Jenny, try to track down the leader of a herd of wild smartcars gone bad. How bad? The cars have "monoed" their drivers (killed them off with carbon monoxide) so that they can roam free, run over pedestrians, and steal fuel. The titular devil car, a black caddy that killed Murdock's brother, has eluded all attempts at capture. He's tricky - repainting himself, keeping a corpse in the driver's seat to look tame, etc.

This one has so many nice touches. It's really worth listening to a few times or once intently to catch all the cool little bits. For instance:

He chuckled.  "Cars actually swear at each other?"
        "Occasionally," she said.  "I imagine the lower sort indulge in it more frequently, especially on freeways and turnpikes when they become congested."
        "Let me hear a swear-word."
        "I will not.  What kind of car do you think I am, anyway?"
        "I'm sorry," said Murdock.  "You're a lady.  I forgot."
        There was an audible click within the radio. 

Here's another example of a throwaway detail that really fleshes in a whole world:

Jenny was a specially designed deathcar, built for him by the Archengineer of the Geeyem Dynasty...

This is Zelazny at his best.

Mind Webs
The Devil Car
20 October 1978
19781020(000)_MWEB_TheDevilCar.mp3
Roger Zelazny (author), Michael Hanson (narrator, Murdock?), Tricia Day (Jenny), Steve Gordon (technical production).

Roger Zelazny