If you’re a Google Android Smartphone or Tablet user, you can take advantage of a service called Google Play Music which allows you to stream your music from the Internet to your mobile device. It’s like your own personal Pandora app, where you can upload all your music to the Google Servers and have it streamed down to your phone or tablet. So if you have unlimited data (like I do with my Sprint cell phone service), streaming music is great since it eliminates the need to store the music files on your mobile device’s local storage.
So I’ve been using Google Play Music while driving in my car, with my music being streamed from my Google account to my phone and through my bluetooth connection with Ford Sync. Works very nicely!