Commuters who travel by bus, train, or even foot may find that the time goes by faster while listening to their favorite music, an audiobook, or the news. And car travelers who don’t have CD players will delight in a portable model that can easily be adapted to work with the car’s existing stereo system. Remember, though, that the car commuter will need a play-without-headphones feature, as wearing headphones while driving is both illegal and dangerous.