The M-body has been named "Bad Penny." Check out the link in my sig to the story on that one.
The '89 Ramcharger is called "the Bus," as in "as big as a..." I started calling my old '79 that. When I replaced the '79 with the '89, the name just carried over.
A buddy of mine in high school started calling my Sport Satellite the Millennium Falcon and the name stuck. The Sport isn't a pretty car. When we got her she was in faded red oxide primer, the fenders had some holes in 'em, the Magnums were faded out and showing some spot rust here and there. But she ran. Good enough that I was the terror of Schuyler County with her. Camaros, Mustangs, 'Vettes, even some of the Porch BMW guys coming into WGI knew of her and would take side streets whenever they saw me coming. So, seeing as how the Millennium Falcon was the "fastest hunk of junk in the galaxy" my buddy named my car after it as being the "fastest hunk of junk in the county."
Somewhere on the car, when I get the resto completed, I'll put the name on.
I've never driven the E-body, as it was given to me as a rolling shell. I'll probably wait until I drive it and see what kind of personality it has before naming it.
The other cars, like my wife's, is just "the" Hyundai, my F250 is "the" F250, etc.