Taking your music with you used to be as easy as popping the cassette out of your home tape player and into your car, boombox, or Walkman. Not so any more. Though the rise of the MP3 has made it possible to download albums in seconds, share them with your friends, and fit millions of songs in a single box, the actual process of getting it from off a desktop hard drive and playing it somewhere else has taken a step backward in simplicity. But that's quickly changing, as a plethora of services and gadgets have sprung up to fill the void. Leave Bon Jovi at home no more. Let's take a look at some of the ways you can get your music off your desktop.