They certainly have 1/4 size DVD players. I keep my Sony ...erm, forget the model number, but it's really weird shaped, like a wedge, with the transport at an angle, is several year old technology, but had a great picture, and 24/96 out on its coaxial.
Here are some others: Samsung, Sony portable, multiregion Sony...well, you can google ("small DVD player" &&/|| "portable dvd player"), yourself, neh?
Sorry, that wasn't very helpful, was it?