<http://schema.org/about>
"Musicians have been making music out of weird and wonderful instruments forever and we have seen many of them:  vegetable orchestras, bicycle parts, ice  and  recycled drains and bed springs.   And now another addition to this"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/culture/the-sound-of-the-earth-is-music-to-some.html>