Spotify - Stream Music for Free. – If you haven’t heard of this yet, then you really should check it out.
DOWNLOAD LINK: http://www.spotify.com/en/download/windows/

You’ll need to sign up, and then login with a username and password. This allows you to be able to access your account on anyone elses spotify and use your saved playlists.

Heres a quick rundown of its features and downsides:

Spotify’s features include:-

• Newly released albums are added to Spotify, impressively quickly.
• You can share songs you like with your friends who also have Spotify, and they can be listening to it right away.
• You can also share entire playlists with your friends in the same way.
• It doesn’t lag, songs play immediately as you click play.

The Downsides:-

• Music can’t be put onto your MP3 player…but did you really expect that feature for free!
• You have to put up with usually quite annoying, thankfully short adverts every 6-8 songs.
• Spotify doesn’t have EVERYTHING in its catalogue. It depends on if the artist’s label has agreed for the music to be made available via Spotify. Artists such as AC/DC and Metallica aren’t on there.

Useful Link: http://www.sharemyplaylists.com/
This website allows you to download other people’s playlists into Spotify, they’re sorted in genre, great to discover new music in your favourite genre’s.