Hi Steve.
I know that you have been looking forward to the Belkin CableFree wireless USB extender as a means of enabling remote, computer-as-source audio, but that product seems to be rather slow in coming. In addition, I've read a few articles that suggest that the underlying Freescale technology may not easily penetrate walls lined with pipes, wires, etc..
I like the concept of a USB DAC powered by a remotely located computer, however, so I was looking around for wired USB extenders and ran across the
Icron USB Rover series of products. These provide a local and remote unit that can be connected with Cat5 Ethernet cable. (One model also allows the use of fibre-optic multimode fiber.) Run lengths for the Cat5 versions can be up to 50m/164 ft. The single port USB Rover 1650 model can be found for $110 online, which is less than the expected CableFree price.
Do you have any reason to believe that something like this wouldn't work at least as well as the Belkin CableFree? (One possible issue might involve the product versions that rely only on the power from the source, rather than a separate power supply.)
Thanks for any comments!