Hi!
I have that idea of a program, I don't know if it exists because I don't know the proper terms to search for. it is very simple but it would be very useful to have. the idea is of a program which listens to a MIC (any microphone), if the sound gets beyond a certain level (above environmental noise), it runs an audio file (it could be a WAVE, no need for an MP3 decoder), and wait for the next elevation in sound level. that's it.
Thank you.