The Rob Fantastic MP3 Encoder uses all the machines on your network to encode wav files to mp3 files. There's a NEW hacked version of the Fraunhofer codec that supports bitrates of up to 320kbits/sec (the old one did 256kbits/sec).
They don't recommend using the Fraunhofer codec with high bit rates, though. It's very good at bitrates 128kbits and below, and very bad at higher bit rates. According to this excellent article on encoding engines, the LAME encoding engine at 256kbits/sec is the best quality MP3 you can produce. Blade is okay at 320 kbits as well. The LAME and Blade encoding engines are included in the download, and are royalty free encoders.