What is your car's rarest option?

cudamark said
I got to thinking about what item I would love to find for my car (1966 Barracuda) that I just couldn't find. I soon realized that most of those items I was able to find if I looked long enough and had enough money to buy it. One item that I still haven't found or even seen a photo of is the optional factory mattress for the rear compartment. Anyone ever seen one or have a photo of one? How about your car? Is there something that was available that you have never seen?

Not exactly a photo, and maybe you already have this, but here's a scanned copy of a xerox copy of the 1965 Chrysler accessory catalog:

07311501 (2).JPG

PS: I've never seen one of these myself, but I can tell you that a single bed mattress will fit just fine if you drop the back seat and the trunk panel