Whether you're the first to buy the newest gadget or a latecomer to the digital-music revolution (What if it's too complicated? What if it doesn't have enough power?), the new DUO-64 Digital E-Cassette from Digisette is a winner. About the size of an ordinary audio cassette tape, the DUO-64 is unobtrusive, attractive, and ingenious. Plug in a set of headphones, and the device functions as a stand-alone MP3 player. Insert the entire unit into any standard cassette deck, and it renders the component MP3 compatible. The DUO-64 comes with 64 MB of onboard flash memory and is upgradable to 128 MB. It also comes loaded with AudibleReady software so that you can access Audible.com's library of more than 17,000 titles of audiobooks and periodicals (now you can listen to Fast Company in your car). And the voice-recording capability lets readers store five hours' worth of voice memos. The DUO-64 retails for $229. Find it online (www.digisette.com).