- max/msp now featuring the jitter video-component was already mentioned
before: http://www.cycling74.com
i reckon that as one of the most flexible solution for both algorithmic
sound and structure generation ; even if it is in some way a programming
language it is quite easy to use because it features an object oriented
environment with a nice gui
- "supercollider" is derived from the c programming language and demands a
bit more sophisticated usage as it lacks the objects and gui. therefore you
get sound-manipulation on molecular level: granular synthesis' favourite.
it is now available as freeware:
http://www.audiosynth.com/
- "soundhack" allows to use any file type (including text, images, video) to
become a source for sound and does a lot more, mainly spectral processing.
it is available for mac (os 9 and X) at
http://www.soundhack.com/
- csound will also perform a lot of weird synthesis stuff:
http://www.csounds.com/