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.
makeself is a small shell script that generates a self-extractable compressed TAR archive from a directory. The resulting file appears as a shell script, and can be launched as is. The archive will then uncompress itself to a temporary directory and an arbitrary command will be executed (for example, an installation script). This is pretty similar to archives generated with WinZip Self-Extractor in the Windows world.
smake is a highly portable 'make' program that makes commands up to date based on rules in Makefiles and on the timestamps of the related files. It implements a complete superset of the features of the classical POSIX/Unix make program. It warns about typical misuse of dynamic macros that prevent portability of makefiles. Its automake features allow you to run scripts to automatically create rules for unknown platforms.
OpenRADIUS is a RADIUS server that allows you to use external data sources for anything - shared secrets, accounts and passwords, profiles, session database, NAS lists, called/calling nr. ACLs, accounting storage, and much more. It has a powerful external module interface that uses pre-spawned subprocesses and pipes for communication, allowing you to implement modules in any language that supports Unix pipe I/O. Its behaviour is fully configurable, using a simple built-in language that gives you full control over the request and reply list. It includes versatile LDAP and SQL modules, a full featured RADIUS client, and a fully functional example configuration for metered pre-paid accounts.
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.
makethumbs is a Bourne shell script which creates static HTML image galleries suitable for web or CDROM presentations. It is designed for portability and depends on the fewest possible helper programs. You can simply run makethumbs in a directory of JPEGs and get a usable set of web pages. If you have the time, you can add captions, descriptions, and create a dotrc file to completely change the look and feel of the generated gallery. A small helper script, rotate.sh, is also available to easily fix rotated images.