A subscription to iTunes Match ($25 a year) means you've got ALL of your music in the cloud. (Sounds poetic.) Store your entire library - even stuff that iTunes has never heard of - on it and access it from all of your devices (iPhone, iPad, iPod touch, Mac, PC, or Apple TV). Each time you open it, it'll scan and make automatic updates so you'll be able to access your up-to-date collection anywhere, anytime. Even better? Stuff that iTunes DOES know doesn't need to be uploaded, so it's faster - and that same music will play back in high quality even if your copy had that yelling-into-a-styrofoam-cup quality.