Beast is a powerful music composition and modular synthesis application. It offers multiple input methods like multitrack, piano roll, and pattern editing and supports skins. On the technical side, it has a wide range of abilities like sequencing, unlimited undo/redo history, real-time synthesis with multiprocessor support, full duplex 32-bit audio rendering, precise timing down to sample granularity, on demand loading of partial wave files, on the fly decoding of various sample formats, aliasing free oscillators, and full Scheme scripting support.
Fresco (formerly Berlin) is an experimental windowing system which is a logical extension of the integrated layout and structured graphics model developed in InterViews and the original Fresco project. It makes heavy use of CORBA for transparent inter-process control, and utilizes a loadable module framework to maintain good drawing speed and extensive customizabillity.
DiaCanvas is a generalized version of the drawing canvas used by DIA. It extends some features used by DIA and adds new ones, while preserving as many of the original features as possible. This project is no longer actively maintained. It is suggested that you try DiaCanvas2 instead.
Fract-O-Rama is a Qt-based fractal generation program. All fractal images are specified using the program's fractal scripting language, so it is possible to explore a wider variety of fractal types/options than with many other generation programs. Full source is included, and the program readily compiles/runs on UNIX or win32 (win32 binaries are also available, as a Qt commercial license is required to build the program on windows). It comes with documentation and many example fractals.
GDAM is real-time digital dj mixing software package. Any number of mp3 files can be played and mixed simultaneously. Effects can be added, changed, and rearranged dynamically. GDAM features a client-server architecture; all sound is produced by a server, which receives instructions from any number of clients. Other features include plugins for audio effects and interface components, cacheing and looping, sequencing, assisted beatmatching, a waveform viewer/beat calculator, contiguous queueing (no pauses between songs when using a playlist), an online help system, an mpg123 clone which runs on a gdam server, flexible command line interface for direct control of server, recording of entire mix or any point in stream to buffer/disk/mp3 encoder, support for multiple sound devices, and support for midi hardware control.
GdkRgb is a rewrite of the image rendering subsystem of Gtk+. Advantages over plain Gtk+ 1.0.x include higher speed, very smooth and pretty dithered modes, and support for more displays and visuals. It is currently checked into development versions of Gtk+ (and used in the development tree of the Gimp), but is also packaged separately for application authors who want to maintain Gtk 1.0.x compatibility. The programming interface is quite simple.