Confusingly, there is also a project called "Common Music" which is a algorithmic composition tool that used to use Common Lisp, but now appears to use Scheme.

http://commonmusic.sourceforge.net/

I actually took a course in college many years ago under the professor who created that application. It's nice to see that it is still under development.

Anything like this in Clojure?

Yes: https://github.com/rosejn/overtone http://vimeo.com/16143967