Windows 7 - How to use a phone's output audio in Windows

Well, I had a grand vision of grandeur. I'm planning on buying a Nokia Lumia 900 running the Windows Phone 7 on it when the phone comes out soon. Being a designer, I had to design a dock to plug in the phone to charge and sync and the idea came: what if I could use my awesome stereo and my awesome Windows 7 to make the dock into an awesome home phone?

What it would be is a mic built into the dock that is connected to the phone so when someone calls me, I don't need to pick the phone up. And if I can with the Windows Phone, I can have the audio out from the call be recognized in Windows 7 as in audio input and I can have my puter's audio output to my awesome stereo to hear the call from my speakers.

The stickler is, as is with every grand vision of grandeur, can it happen? I don't know for sure what to do to get the audio out from the phone to connect with Windows 7.

So basically, can this situation happen?!

Thanks!

I don't know if it can be done though the USB connector, but I do know it can be done though Bluetooth.

Yeah, I was thinking that it could only be done through bluetooth...