Like jjmartin said, a very popular accessory in Japan, especially in taxis (where it's an almost obligatory feature) as well as private cars. Actually, come to think of it, most of the SE Asian countries I've visited have an abundance of the bloody things.
I think my grandmother used to call them antimacassars*. Blimey, showing my age there.

*Question of the day gentlemen: What's a macassar and what is the 'anti' bit preventing? Answers on a postcard please...