Is there any way I could have a processing sketch pull live sound and transmit it via USB to the arduino?
The Arduino doesn't necessarily have to do anything to the sound.
I ask this because I have a USB Headphone and I also want speakers to play sound at the same time my headphones do. Windows 7 won't allow me this flexibility. Can the arduino do such a thing?
Thank you. 
Windows 7 won't allow me this flexibility
Nahh but there's some program that lets you do this. Can't remember what it's called. It also lets you use the mic input as a speaker/headphone output.
Maybe someone else knows what it's called.
I've tried it. It needs to be on all the time. Well then again, so do processing sketches....
Sigh... :-/
I've tried it. It needs to be on all the time.
Surely it will just sit minimised on the notification bar and won't affect you...
You have no idea how paranoid I get at little things. It's like I have this compelling subconscious bugging me about things not being perfect enough.
;D
No really.