A digital replacement for the cassette tape player that few people have gotten a good look at, since it's only given out to blind and visually impaired people by the Library of Congress' National Library Service. Introduced in 2009, the DS1 standard and DA1 advanced digital talking book players use cartridges and USB thumb drives to play audio books and music.

For those asking for a teardown: I wish I could oblige, but the case has two deeply recessed Torx screws, and neither of my two sets of Torx bits are long and thin enough to reach them, so I am unable to take it apart.