Picked up a Sony JB920 a few years ago. Used it in D/A mode (pressed record with no disc)and fed it with an AV710 and a decent glass toslink. Unfortunately, the deck resampled all input to 48000 Hz, but it did have a 24bit DAC - sounded pretty damn good for what it was, very similar to the Rotel RCD-950 I used to own. Well, maybe just a smidge better. Headphone jack on it sucked, though.
Getting to the point, the older higher end decks (JB and ES series) can make a great, cheap DA converter. As for the disks themselves, I used to use them, but mp3 players are so damn small now.