I know you've been able to nick stuff off the internet for years and that I was just never into that when loads of others were but....
Spotify really is the dog's bollocks. Like having your own music shop of great tunes and legally. You can do it for free with ads or pay a tenner a month which means no ads and more importantly allows you have offline playlists accessible in a smartphone app. Great selection and variety of music too - I'm listening to all sorts of stuff I'd never have been willing to risk a fiver on if I'd seen a bargain bucket CD of their work. Tends not to have much from your giant rock bands (Led Zep, AC/DC, Beatles etc) but chances are if you like them you'll have that stuff anyway. Can see myself being a lifelong customer of it from here on.