Exaile is a Gtk+ music player with a simple interface. It allows powerful music management, has smart playlists, tagging features, can display album art and lyrics. It can also connect to streaming servers, download podcasts. Exaile supports secondary output devices, and there are over 50 extension plugins. It's available cross-platform.
Universal Media Server is a DLNA-compliant UPnP Media Server, which is implemented in Java and thus runs on all operating systems. It can convert any media file format, and stream it to a wide range of hardware devices (smart TVs, and media centers).
Red5 is an Open Source Flash Server written in Java that supports streaming Video (FLV, F4V, MP4, 3GP), streaming Audio (MP3, F4A, M4A, AAC), recording Client Streams (FLV and AVC+AAC in FLV container), shared objects, live stream publishing, remoting and protocols RTMP, RTMPT, RTMPS, RTMPE. Additional features supported via plugin: WebSocket (ws and wss), RTSP (From Axis-type cameras) and HLS.
ICEcast is a audio/video streaming media server. Which supports Ogg Vorbis, Ogg Theora, FLAC over Ogg, Opus, Speex in Ogg, WebM and MP3 audio streams. It's widely used for setting up public internet radio stations, or local jukebox servers. ICEcast is flexible and extensible with new media formats and functionality.
Spdwn is a shell script for streaming Southpark episodes using rtmpdump. It avoids utilizing the browser-based flash player. It further only requires curl or wget, and rtmpdump
butt (broadcast using this tool) is a Shoutcast and Icecast streaming tool, which runs on Linux, Max OS X, and Windows. It's primarily meant for broadcasting live audio data, directly from line or microphone input. It's not intended as streaming or playlist server by itself.
A music jukebox app that disguises itself as an iTunes replacement without all the extra baggage, but is actually a web-first, fully streaming, anti-cloud, social music server that allows multiple people to listen to the same stream of music at the same time and DJ for each other. Kinda like a private turntable.fm.
Tomahawk is a music player and audio streaming service frontend for desktop usage. It manages songs, albums, playlists, meta info, social sharing. It supports various cloud services and commercial providers, such as Spotify, Beats, Google play, Soundcloud, LastFM, Hype Machine, Echo Nest, Rdio, Grooveshark, Billboard, OwnCloud, iTunes, Jamendo, Deezer, Ampache, Jabber, and Subsonic.