If you have an internet connection, a decent one, the trick is grooveshark.com.
The word goes that currently it has a database of around 22 million songs, the biggest to this date and yes it is user based content network, the only way taking into account the impressive number of songs available.
You can find almost any song you might want to listen, the streaming servers are fast enough, the quality for most of the songs is pretty good and you can create playlists and save them for later sessions. If you ask me, that’s almost everything one needs to enjoy his preferred songs at anytime.
Grooveshark, the way i see it, it’s like the ultimate personal internet radio or the ultimate free itunes library. 😉
It’s perfect for listening to your favourite music at work or in any other places where your music collection is not at hand but an internet connection is.
Don’t ask me how come it is still up or legal, word is that grooveshark pays licenses from the ads revenues to the record disks that complain or act against it and it seems to suffice, at least for the time being.