I used to play sonic 2 just to hear the Metropolis zone music.
I think I even used a tape recorder so I could listen to it away from the game.
I also remember a speciffic time when I heard "the lion king" playing in my genesis, but I was nowhere near it. Apparently my mom liked the music, so she put the game in to listen to the menu music. I tried to explain sound test, but it was a bit too much for her.