A better idea would be one of those "Rabbits" for audio -- the input is a line level source [which you could attach to the] speaker output of one PC -- this PC could recieve the shoutcast, it could even be the live source].
The ouput is via wireless transmitter that has recievers which supply a line out source that can be placed by other audio equipment with a line input [an amp, A/V reciever, your TV, a VCR, a PC...].
There are also similar devices that use your in-house AC wiring to transmit the audio signal between rooms.
It's similar to a "baby monitor" for audio , but without speakers...
I think the price is close to what you're looking for. I really forget where I saw it -- J&R, Sharper Image, Radio Shack maybe?
If you have various devices around your house recieving a stream through the network, you would have a terrible echo effect whenever you could hear any two at the same time, that would get worse with the more devices you have "listening."