I'd like to add to this discussion by mentioning the ChucK music programming language (http://chuck.cs.princeton.edu/ http://chuck.cs.princeton.edu/). Here is a

I'd like to add to this discussion by mentioning the ChucK music programming language (http://chuck.cs.princeton.edu/ http://chuck.cs.princeton.edu/). Here is a TedX talk by the co-author, Ge Wang, talking about the joys of digital instruments (http://www.ted.com/talks/ge_wang_the_diy_orchestra_of_the_future http://www.ted.com/talks/ge_wang_the_diy_orchestra_of_the_fu...). In the talk, Ge Wang talks about leading the Stanford Laptop Orchestra, which uses ChucK to program all sorts of crazy digital instruments, and also talks about "Ocarina" iPhone instrument. Cool stuff!