(YouTube Link)
Linsey Pollak, Brendan Hook, and Ric Halstead comprise The Cycologists, an Australian band that bases its preformances on a bicycle theme. They've fitted their instruments into their bicycles, as the video above demonstrates when the musicians use their seats as clarinets. Other instruments include tuned bicycle bells, flutes that work as handlebars, and panpipes powered by tire pumps. The Cycologists' stage shows are quite complex and you can see videos of them at the link.
Link
http://www.youtube.com/watch?v=8e3I0iagWXU&feature=related
I really liked the last 3 videos on their site.