There is two ways of background music, MIDI or Real Audio:

Lots of links to MIDI-files:
 

Get the new RealPlayer 4.0 beta.
Now one RealPlayer plays RealAudio and RealVideo. Get the
free RealPlayer or the full-featured RealPlayer Plus here:


Listen to a few classical
masterpieces in STEREO: (linking does not always work!)








Four Seasons
Vivaldi

Eine Kleine Nachtmusik
Mozart

Drottningholm Music
Roman

Lots of links to live Real audio/video stations: