Today Steve Lynch and I did some exploring off Peñasquitos Park and came across these derelict cars dropped into a small gorge. A VW Beetle, Audi and Ford Explorer (high gas prices, you know) were ones I could identify. There were two others rusted beyond recognition. It looked like after the cars had been shoved into the pit, they had been sledgehammered, to make sure they were really dead, of course. The Beetle was missing its motor, among other things, while the Ford didn't have any seats in it. The Audi was probably a nice car once upon a time, it had a sun roof (or moon depending on trademarks).
I like to imagine this is what might happen if the world order collapses. People just junking once useful and valuable things when you can no longer get gasoline or electricity. Kind of like Mexico.
Update: you can see the Ford on Google Maps.