Evolvotron is an interactive "generative art" application to evolve images/textures/patterns through an iterative process of random mutation and user-selection driven evolution. If you like lava lamps, and never got tired of the Mandelbrot set, this could be the software for you. It's implemented using Qt, and is multithreaded.
Gnofract 4D is a Gnome-based program to draw fractals. What sets it apart from other fractal programs (and makes it "4D") is the way that it treats the Mandelbrot and Julia sets as different views of the same four-dimensional fractal object. It contains a Fractint-compatible formula compiler, allowing it to draw an unlimited number of fractal types, using numerous coloring options.
alph implements and analyzes historical and traditional ciphers and codes, such as polyalphabetic, substitutional, and mixed employing human-reconstructable algorithms. It provides a pipe filter interface in order to encrypt and decrypt block text to achieve transparency. The program is meant to be used in conjunction with external programs that transfer data, resulting in transparent encryption or decryption of information. The program can thus be used as a mail filter, IRC filter, IM filter, and so on.
FrAid (Fr[actal] Aid) is a programming language that is appropriate for mathematical computations, visualization, batch processing, and more. It features both a standalone application that provides a programming environment for the language and a system for integrating the language with Java. The Java interface allows mathematical equations and formulas to be used with Java code, making it easier to process numerical computations, symbolic computations, imaging, CAD, and more.
DJFractal is yet another fractal generator which distributes fractal data to multiple computers. Fractal data are created locally and distributed to other computers that run the appropriate fractal-generation software, which may be hosted on workstations, or on a Java enabled Web-browser through applets, or on a system with JavaCard. DJFractal's unique feature is the "smart" algorithm it uses to compute (and draw) the most interesting part of a fractal first.
Pulga is a program for numerical simulation of dynamical systems. It is designed to provide a way for students and researchers who study dynamical systems to model them on a computer and analyze them numerically without the difficulty of traditional computer programming languages.