huh?

it's actually Japanese toll pass (as per MC@MYGTR)

Okay, my son came over and we both looked at it. He believes that it is for flash cards, and so do I. The photograph is on the right side of the dash so you can just see the hood release area, placing scale to where it is located; it is too small for a MiniDisc.

There are two (2) slots:

1) The top looks to accommodate a Compact Flash Microdrive card (ejected with the eject button on the far left side).

2) The lower slot is an MMC card (to remove this card simply use the provided finger slots).

Here's a picture of the ETC (Electronic Tool Collection System):

I think SoCal is correct. This looks like a flash card reader.

SoCal is totally correct.
In Japan this is very common to be in a car :P

--Shunya