Recently I got a Nokia N800 which is great because it has wifi and and a great soundcard (even great speakers for a device of this size): it's begging to be a portable WIFI boombox.
The only problem is that MPD only supports Ogg vorbis through Icecast. Ogg vorbis is available through alsa applications on the N800 but most of the applications on the N800 are not alsa aware, which means that the nice little desktop applet for media streams won't communicate with MPD/Icecast.
I figured out recently that MPD CAN stream in Mp3 format (albeit in a bit of an indirect fashion):
The process was a little bit involved but not too terribly difficult once I figured out the correct pipeline. It's late and I don't really feel like writing up the whole process. If anyone is interested, make a comment and I'll post some more details.