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.
Cactus is a general, modular, parallel environment for solving systems of partial differential equations. The code has been developed over many years by a large international collaboration of numerical relativity and computational science research groups and can be used to provide a portable platform for solving any system of partial differential equations.
EGO is a program to perform molecular dynamics simulations on parallel as well as on sequential computers. Supported parallel machines include the Hitachi SR8000, CRAY-T3E, IBM-SP2, Fujitsu VPP700, Parsytec-CC under PARIX, and inhomogeneous clusters of UNIX workstations under PVM or MPI. EGO also runs sequentially on any decent UNIX workstation, even Windows95/NT PC's (with a GNU-C compiler) can be used.
GNU TeXmacs is a free wysiwyw (what you see is what you want) editing platform with special features for scientists. The software aims to provide a unified and user friendly framework for editing structured documents with different types of content: text, mathematics, graphics, interactive content. TeXmacs can also be used as an interface to many external systems for computer algebra, numerical analysis, and statistics. New presentation styles can be written by the user and new features can be added to the editor using Scheme.
PLOTICUS is a command line utility for creating bar, line, pie, boxplot, scatterplot, sweep, heatmap, vector, timeline, Venn diagrams, and other types of charts and plots. ploticus is good for automated or just-in-time graph generation. It handles date, time, and categorical data nicely, and has some basic statistical capabilities. It can output to GIF, PNG, SVG, SWF, JPEG, PostScript, EPS, and X11. You can use convenient preset options or create complex scripts with rich and detailed color and style operations.
The Snack sound extension adds commands for sound play/record and sound visualization, e.g. waveforms and spectrograms. It supports in- memory sound objects, file based audio, streaming audio, WAV, AU, AIFF, and MP3 file formats, synchronous and asynchronous playback. The visualization canvas item types update in real-time and can output postscript. New commands and file formats can be added using the Snack C-API.
Viewmol is a program for building and editing molecules as well as for the visualization of outputs from quantum chemical and molecular mechanics programs. Currently supported are Gaussian 9x, Gamess, Discover, DMol/DSolid/DMol3, Gulp, Mopac, Turbomole, and PDB files. Properties visualized include geometry (with various drawing modes), vibration (animated or with arrows), optimization history/MD trajectories, MO energy level diagram, MOs, basis functions, and electron density. Drawings can be saved as TIFF, HPGL, Postscript, and input files for Rayshade. Viewmol has an embedded Python interpreter for automation. The program is language independent and currently "speaks" English, French, German, Russian, or Spanish.