Icecast is a streaming media (audio/video) server which currently supports Ogg (Vorbis and Theora), Opus, WebM and MP3 streams. It can be used to create an Internet radio station or a privately running jukebox and many things in between.
IceS is a source client for the Icecast streaming server. IceS-ne is a deeply redesigned old IceS 0.x project. It supports sending an MP3 stream to an Icecast server from local files and playlists.
IceS 2.x supports sending an Ogg Vorbis stream to an Icecast server. This source client is well suited for broadcasting digitized sound in real time.
See icecast.org for more information.