Dataplay is a digital storage medium created by the company of the same name. According to the FAQs on the website (http://www.dataplay.com) the devices which support this technology will be released starting in 2001 (now). Each DataPlay disk is the size of a quarter and can store up to 500 megabytes. The disks are write-once. Dataplay also created a reader (which is to be incorporated into other consumer devices) called "Dataplay micro-optical engine" which is supposed to have a "very-large" buffer and work 10 hours on a single AA battery. As far as I can tell there are no real devices out there at his point in time that use this technology, even though it has been show-cased on 2001 CES - vapourware.

More info @ www.dataplay.com