For users of Squeezebox Server, there exists a light program called SqueezeSlave that can be very easily used to mirror the output of a Squeezebox Radio on a computer.
It’s available for download from http://code.google.com/p/squeezeslave/ and more information is available from http://wiki.slimdevices.com/index.php/SqueezeSlave. It’s available for OSX and Linux, and builds from source and works well on FreeBSD too.
It’s pretty simple to use; simply run it with the IP address of the Squeezebox Server, then go into the Sqeezebox Server web interface and tell it to synchronise the Squeezebox Radio with squeezeslave (once you have the latter running).
I run squeezeslave on my primary FreeBSD machine which feeds my hifi through a DAC, synchronised to my Squeezebox Radio in my kitchen, allowing me to wonder about and hear my podcasts continually. Bonza!