One of the planed features for the OggStreamer is the integration of a small Java/Flash OggPlayer – which can be started directly from the builtin webinterface. Stumbling accross the Internet i found a very cute piece of Software doing exactly that task: FFMp3 – it is Flashbased and licensed under GPL2. The software is quite slim as well: around 150 kBytes (including graphics for the skin). And it is compatible with both Shoutcast and IceCast2-Servers.
Software can be found under: http://ffmp3.sourceforge.net/