MP3 players; GPS receivers; E-Book readers
Higher-end models could be a waste
People still buy them by the truckload, but as smartphones become ever more capable, the utility of carrying a separate device that only plays music (and, in most cases, photos and movies) continues to decline. That makes buying a higher-end model seem like a mistake. If you already use Apple's iTunes, your best option is that company's just-updated iPod Nano, which adds an FM tuner and a video camera. If you're not in the iTunes camp, Microsoft's Zune HD offers the closest equivalent to Apple's integration of hardware and software, plus the ability to tune into digital-only HD Radio over-the-air broadcasts -- but make sure you buy only MP3s at its Zune Marketplace, not Windows Media files locked down with usage restrictions. If you run Windows, you can spend a fair amount less on Windows Media Player-compatible music players sold by such companies as Sandisk.
Less is more with dedicated hardware
Smartphones and their mapping programs were already making stand-alone GPS units appear somewhat obsolete before add-on driving-directions programs for the iPhone and the Google navigation software on Verizon's Droid made dedicated navigation hardware look outright doomed. My advice here is to spend as little as possible; in particular, don't be too tempted by extra services bundled on higher-end models.
Words of caution before jumping in
Amazon's Kindle dominates this category but continues to suffer from self-imposed compatibility problems -- the usage controls Amazon embeds in its e-books prevent you from using them in hardware or software not approved by the Seattle retailer and also forbid such customary practices as lending your copy to a friend. Its e-ink screen, meanwhile, exhibits the slow performance and low resolution of an early effort. A crop of new e-book readers -- for example, Barnes & Noble's Nook, Plastic Logic's Que and Sony's Reader Daily Edition -- promise better features but won't ship until the end of this year or even later. If you simply cannot live without an e-reader, get Amazon's basic Kindle model, not its bigger Kindle DX-- but realize that a few months from now you may regret jumping into this market too soon.