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.
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.
geo-* is a set of tools for geocaching, including tools for accessing the www.geocaching.com, opencaching.com, opencaching.us, and navicache.com websites, tools for geocoding addresses and creating maps, and tools for manipulating Mapopolis place guide data. The focus of these tools is to provide a command line driven environment.
Brace is a dialect of C that looks like Python. It has coroutines, hygenic macros, header generation, and libraries with graphics and sound. It is meant to be good for beginners, kids, and experts. Brace is translated to C, then compiled, with #! support and cached executables. It is fairly portable, and runs on GNU/Linux, Unix, and Windows with MinGW. It should also run on Mac OS X. It comes with a lot of demo programs, many with animated graphics.