Mintek MDP-5861 5-Inch Portable DVD Player
cheap but good
This little thing was a life saver on our 13 state trip this summer.  We did have trouble with the first one we bought because the eject button pushed inside the unit and we had to break into it to get our DVD out.  Target replaced it and we have had it ever since.  We did have trouble in one car, my dad's girlfriend's Cadillac where it would play the picture for only a little time but play all of the sound. Then the picture went away.  We never investigated fully because it has worked in all other cars.  I think it is because the Cadillac was pushing the power plug out like it was a lighter and only would stay in part way.  I have hooked it into my TV at work and my TV in the play room at home.  Both times it worked without any problems.  The battery came with ours and it helped when we were stuck in the middle of nowhere without power.  The battery lasted long enough to watch a full length movie.  When watching the beginning of another it said low battery and quit after about 15 minutes.  I thought the screen would be too small for the kids to appreciate but it was plenty big, especially in the back seat when it was dark out.  The speakers are a little tinny sounding so it might be better to get headphones and a splitter to have multiple listeners.  Overall I would say that it is probably not the best but certainly the cheapest I have ever seen.