Airtunes using "virtual" airport. (1 Mac and 1 PC's)

Hi,

On may Mac i have stored all my music and media. I have just set up a new speaker system at the other side of my house running of a pc with windows xp. I wish to play music from my mac on both the computers at the same time. As i already had a computer there I was wondering if there were any such applications that would do the job of an airport express?

Thanks for any help.

I think the closest you'll get is something like EsounD or Network Audio System which can be used as network based soundcards. I don't have any experience with setting up either of them so I can only point you towards Google.