I added an AVIO digital to analog adapter which is connected to my switch and then to my amp, so I can send system sounds from my laptop through the network and direct them to any area in the house.
The ultimate reason I wanted this was because I want to be able to send audio from my DAW, i.e. piano/organ and other plug-in sounds triggered by my piano to any given zone in the house without needing an additional sound system.
My office will receive a feed from the house amp to the overhead speakers so I can use those speakers overhead for a quick reference, or to play for the family, etc.
Any other creative uses out there?