Running digital cable 40' long out of the Hag-usb. I don't usually run audio thru a 40' cable, but it was already installed in the wall from my PC to my HT so I gave it a try and was surprised at the result. I recently purchased a DAC-AH that I will try as soon as I run it in.
Belkin has a wireless usb hub coming out this summer. Looks promising for a long distance solution. I plan on gettin one and will post the results of it here.