distributed.net is a loosely knit group of computer users from all of the world that is taking up challenges requiring lots of computing power (most notably the RC5, DES, and OGR cracking contests). It is simple to participate in the challenges by downloading and running their client software (which uses idle CPU time to complete its tasks).
hp2xx is a versatile tool to convert vector-oriented graphics data given in Hewlett-Packard's HP-GL (a.k.a. HPGL) plotter language into a variety of popular both vector- and raster-oriented graphics formats. The various supported output formats include Encapsulated PostScript (EPS), PCX, IMG, and several formats intended to facilitate the generation of graphics within TeX documents. In addition, hp2xx output is printable on the HP Laserjet/Deskjet printer series, and it may be used as a HP-GL previewer on many platforms, e.g. X11 and DOS (VGA).
Survex is a software suite for processing, viewing, and printing cave survey data. It is multi-platform and multi-lingual, can deal with extremely large and complex datasets, and can read survey data from many sources. A sophisticated GUI visualization tool (Aven) is included as well as the data processing tool (Cavern) and a data entry tool (Survex-edit). There are also printing and data conversion tools. Printing for HPGL, Postscript, PCL (Laser/inkjet), and Dot-matrix printers is supported. Output converters to DXF and extended elevation form are included. Survey data can be read in native Survex form, or Compass or CMAP files. Conversion from other formats such as SMAPS is easily accommodated.
JSBSim is a multi-platform flight dynamics model. The FDM is essentially the physics/math model that defines the movement of an aircraft under the forces and moments applied to it using the various control mechanisms and from the forces of nature. JSBSim has no native graphics. It can be run by itself as a standalone program, taking input from a script file and various aircraft configuration files, or it can be run as an integrated part of a larger flight simulator implementation that includes a visual system. The most notable usage example is the FlightGear simulator. JSBSim models the aerodynamic forces and moments by the classic coefficient buildup method.
Gri is an extensible plotting program designed for scientists. It can draw x-y plots, contour plots, and image plots, and has rudimentary programming capabilities. Output is PostScript. Gri is not mouse driven, nor GUI-based; it is a language. Users regard it as an analogue to the LaTeX document formatting language: users gain considerable power, at the price of a moderate learning curve.
PACT is a self-contained set of tools which support developing and using portable programs, particularly scientific and engineering applications. By defining a single, higher level, standard programming interface, it shields application developers from the plethora of different hardware architectures and operating systems and their non-standard features.