Art of Illusion - - Art of Illusion is a 3D-modeller, renderer and raytracer. It is written in Java and runs on Linux, Solaris, OS X, and Windows.
Cinelerra CV - - The community developed version of this non-linear video editor. Documentation in several languages.
Cthugha Development Page - - "An Oscilloscope On Acid" - Cthugha also lets you save certain visualizations to keystrokes which makes it a great tool for VJs.
GStreamer - - A multimedia framework with a plugin based architecture for a variety of platforms including Linux, Windows and OSX. Site has downloads, developer resources, and links to applications using the framework.
Heroine Virtual Ltd. - - The original developer of Cinelerra provides that video editor and other multimedia programs and utilities.
IceWM Control Panel - - A Gtk-based sound events and sound theme manager for IceWM that does not require Gnome.
The Linux MP3-HOWTO - - Describes the hardware, software and procedures needed to encode, play, mix and stream MP3 sound files.
Matan Ziv-Av - - zgv, svgalib, and other Linux projects.
MPlayerXP - - MplayerXP is branch of the well-known mplayer which is based on a new, thread-based core. The new core provides better CPU utilization and improves performance of video decoding.