Raspberry Pi model B - Live mp3 streaming from audio-in with DarkIce and Icecast2 on Raspberry Pi
Total cost for the feed computer then was under (US) $60 even
including shipping. If you have a 4 gig SD card and/or USB charger
already then it would even be less. And as a bonus the RPi only uses 5
watts and is silent (no fan). Not bad considering that the computer it
replaced used 115 watts or more and put out more heat than the exhaust
on a double tractor trailer rig.
My setup is a Raspberry Pi running headless (no keyboard or mouse) with
700 ma USB power supply (an old Motorola phone charger). It is
connected to my router / cable modem with an Ethernet cable (i.e. not
using USB WiFi dongle). The scanner audio output is fed to a USB
soundcard like this one: