SIDPlayer is a replayer program for C64 music (SID tunes), running under BeOS and Unix. You can think of it as being a stripped-down C64 emulator that only emulates the CPU and the sound chip of the C64. SIDPlayer can be used as a stand-alone player or, under BeOS, as a plug-in for CL-Amp and SoundPlay.
SmartPlay is a Perl/GTK-based mpg123 frontend with a pseudo-artificial intelligence. Its user interface is very efficent, and it tries to learn from your past listening patterns in order to predict what you want to hear. Both the user interface and AI are designed to minimize the amount of time you spend skipping songs you are not in the mood to hear.
SoundTracker is a pattern-oriented music editor (similar to the DOS program 'FastTracker'). Samples are lined up on tracks and patterns which are then arranged to a song. Supported module formats are XM and MOD; the player code is the one from OpenCP. A basic sample recorder and editor is also included.
SoX is the Swiss Army knife of sound processing tools: it can convert sound files between many different file formats and audio devices, and can apply many sound effects and transformations, as well as doing basic analysis and providing input to more capable analysis and plotting tools.
stream-db is a database-enabled version of streamcast, an MP3 file streamer for icecast/shoutcast servers. stream-db uses a database for the backend instead of perl data structures. The database holds song information, play queues, event logs and request logs. The aim the project is to allow people to create their own streaming media stations, with users, requests, song histories, and playlists and other such fun things.
Streamripper records MP3, Ogg, AAC, and NSV audio and video files from Shoutcast and Icecast compatible streams. The streams can be recorded as a whole or in individual tracks. Streamripper also features a relay stream, which lets you listen or watch live from multiple clients while recording.