OpenSound Control
I have been investigating a bit of OpenSound Control for purposes of integrating my software with those of others. If the visual software had a decent OpenSound Control server, it could mean for instance collaborations with people running Pure Data. But not much is written as we speak aside from some preliminary tests. Anyway, here are some relevant links about OSC.
http://www.cnmat.berkeley.edu/OpenSoundControl/
http://www.cnmat.berkeley.edu/OpenSoundControl/clients/sendOSC.html
http://www.cnmat.berkeley.edu/OpenSoundControl/dumpOSC.html
http://www.cnmat.berkeley.edu/OpenSoundControl/OSC-spec-examples.html
http://barely.a.live.fm/pd/OSC/index2.html