Aeonix 71 Posting Whiz

I know that it's possible for speakers to repeat whatever sound comes into microphone.

But, now I'm thinking. When I speak on Skype/TeamSpeak (VoIP software), would it be possible for me, to select audiofile and play it as if it was sent through microphone?

To send music through my "microphone" and microphone has no actual involvment, but software is managing it this way, that every program that listens to my microphone, gets to hear the sound in high quality (higher*).

Of course I could give them link, or title, but still, I'm heavily interested whether it's possible.

(question involves Linux, any custom type really, Ubuntu, Arch, Slackware, what you not)