Alt Bike Culture - push the pedals and music plays

I'm interested in making a music-playing bike for an upcoming arts festival.

I've seen posts on here about stereos for blasting music from an mp3 player. This is not what I am asking about.

I'm asking about creating a mechanism where notes would sound as the cyclist pedaled and the wheels moved. I've seen versions of this (like the guitar windmill at Makerfaire Austin 2008). I remember talking to an engineer friend about how to make it work years ago, and he said I should look into "ionian harps," but I can't find anything relevant to my project.

Just going to repeat this: This would NOT be for street-riding. I understand that riding this around a campus or road could disturb other commuterse. This mechanism would specifically be for an arts festival where people would be expecting lots of loud music and noisemakers and such from all directions.

Aeolian harps sound by wind power alone. http://en.wikipedia.org/wiki/Aeolian_harp

Maybe some percussion instruments activated by a camshaft driven off the rear wheel. Look at old-fashioned music box mechanisms for inspiration.

Sounds like a cool project.

you could maybe have trigger strips pointing to the wheel spokes. then when the wheel goes round. they move the triggers and make the sound.
be like a music box
I suppose that you could put something like a reflector on the spokes. so it triggers the sound at a specific place. not 36 times on a revolution

Could you do something with a vinyl record player type setup only sideways? The music might not be exactly dolby surround but it would probably make some sort of noise. Maybe a chime or xylophone conversion?

Could there be some electro-magnetic sensors, similar to that used by your speedo, and when a magnet attached to the spokes passes by the sensor, it puts out a signal, and attached to sensor is some kind of musical actuator. It would be like a giant music box.

Sensors on both sides of the bike would let you play two tunes.