DataPlay is also the name of my new mp3 player. Not surprisingly, it uses the dataplay media discs described in the above writeup. Produced by Classic, a very excellent mp3 player manufacturer, this device is available at Circuit City for $199.99. Mine came with a $30 rebate as well. It contained 1 DataPlay disc and there was also a pack of 3 more discs for $34.99 available.
So far, I would consider this a really good form of storage medium. It is worth mentioning that the dataplay disc is two-sided, with 250 megs of storage on each side. The DataPlay mp3 player is packaged with software required to play any stored mp3s, but as far as I can tell you can also store a variety of files on the dataplay disc for purposes of transfer. When the mp3 player is connected to my computer via USB, it appears as a separate drive number. However, any music I placed into it didn't register when the player was activated.
One small setback I have discovered concerning the dataplay discs is that they are hard to label... they are tiny, and the small white paper sticker on the otherwise transparent discs is even tinier.