My house has speakers in every room which I control via Control4 (there’s an iPad and iPhone app for it as well). Connected to Control 4 I have an Apple TV 2. 

On my box downstairs I have iTunes with all my music. And on my PC here at my home office where I program, I have iTunes able to access those songs via iTunes’s home sharing.

Then, using Airplay, I have it play my songs through my office speakers. 

Now, If only I could get my PC games to play their sound through iTunes.