I have never heard of one, though I'd be one of the first one to get one when it comes out. In theory, a portable dvd player that plays mp3's should be able to play mp3's burned on a DVD provided that you have a DVD burner.
FYI: I have herd DVD+R is much more compatible to DVD players than DVD-R. Also RW DVDs don't work well with DVD players, especially older ones. Also stick with major brands: imation, TDK, etc. Some generic brands work fine, others don't work well.
i have heard of them yes. i cannot say a product name or anything but i know they exist (now). saw it on tech TV
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