Music Player Daemon (MPD) is a server that allows remote access for playing music in various formats and managing playlists. It makes a great desktop player with frontend options (Qt, GTK, ncurses, Windows, and Web clients are available). It is also appropriate as a console player that is scriptable, and is especially useful if X is restarted frequently. A set of rapid development tools for clients are being developed and include a C library, Python module, PHP class, Perl module, and Java Class. The goals are to be easy to install and use, to have minimal resource requirements, to be stable and flexible, and easy to interface.
XMMS-SID is an XMMS1 plugin which provides support for playing the so-called "SID tunes". It uses the libSIDPlay1 and/or libSIDPlay2 emulator engines, which provide a virtual emulation/simulation of the Commodore 64 computer and its SID sound chip. It features a file info window, support for STIL database, a song length database, and good configurability.
Wine is an implementation of the Windows API on top of X and Unix. It does not require Microsoft Windows, but can use native Windows DLLs if they are available. It provides both a development toolkit for porting Windows source code to Unix as well as a program loader, allowing many unmodified Windows programs to run on x86-based Unixes.
xCHM is a cross-platform GUI frontend for CHMLIB, written with wxGTK. It is able to display the topics tree, work with displayed pages history, print the current page, work with bookmarks, change fonts and fast search through all the pages of the loaded .chm document. Being indirectly dependent on GTK+, the possibility of changing GTK+ skins makes xCHM theme-friendly.
DarkIce is a live audio streamer. It records audio from an audio interface (e.g. a sound card), encodes it, and sends it to a streaming server. DarkIce can record from OSS audio devices, ALSA audio devices, Solaris audio interfaces, and Jack sources. DarkIce can encode into MP3, MP2, Ogg Vorbis, and AAC formats, and can send the encoded stream to ShoutCast, IceCast 1.3.x and 2.x, and the Darwin Streaming Server.
BRL-CAD is a powerful constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, and image and signal-processing tools.
xine is a free multimedia player. It plays back CDs, DVDs, and VCDs. It also decodes multimedia files like AVI, MOV, WMV, and MP3 from local disk drives, and displays multimedia streamed over the Internet. It interprets many of the most common multimedia formats available--and some of the most uncommon formats, too. All those features come in a reusable library (xine-lib) which can easily be embedded in your applications.
SaVi is satellite visualization software that lets you create, run, examine, and modify satellite orbits in two and three dimensions. Simulations of Iridium, Globalstar, Galileo, GPS, and other satellite constellations are included. SaVi requires Tcl and Tk on a system with Unix libraries. SaVi works well with the 3D renderer Geomview. Geomview is optional, though recommended for its 3D rendering capabilities.