Some of the most surreal and original computer games over the history of console and PC gaming have involved mixing musical elements with engaging visuals and/or artwork.
I'm in the process of investigating a selection of games that involve the player with music in some way.
Some of the games have the player actually contributing to the music - with each button press triggering a sound... example: DJ Max Portable/Guitar Hero
...all the way through to the music merely being used as an indicator of the player's progress through the game where the music 'builds'... example: Rez
Finally, there are some games where music creation is the only purpose. I won't be focussing too much on this sort of music game - because there isn't really a 'game' element. The player doesn't progress in any way and there aren't any goals or challenges.