f/Calc is a utility to calculate lens formulae for photographers so you can focus on the artistic bits rather than on the mathematics behind it all. f/Calc can do "f" number arithmetic, and can calculate depth of field, hyperfocal distance, the field of view of a lens, the angle of view of a lens, magnification, and how the focal length of the lens on the camera changes the way the spot metering function works. In addition to the Unix/Linux Tcl/Tk version, there are native Windows, Palm OS, and Macintosh versions as well.
Ficl (Forth inspired command language) is an ANS Forth interpreter written in C. Unlike traditional Forths, this interpreter is designed to be embedded into other systems as a command/macro/development prototype language. Ficl provides object extensions that can be used to wrap methods and structures of the host system without altering them.
SmallBASIC is a free interpreter for BASIC, a simple computer language, targeting simplicity, mathematics, and graphics. Also, it has a powerfull string library, supports external C modules (shared libs), uses dynamic arrays (by default) and has no data types. Versions exists for Linux (or other Unix), PalmOS, DOS, Win32, VTOS (Helio), and Franklins (eBookman). It uses a lot of drivers, including svgalib, ncurses, and framebuffer.
The par utility creates and manipulates PalmOS database (.pdb) and resource (.prc) files. Par is designed to be a Swiss army knife for managing these files. It's a command line tool, and not for the faint of heart, but it's very handy and replaces a bunch of little utilities that you might otherwise use.
The Helix Ribosome build system is a set of programs written in the Python programming language which provide a common interface to retrieving and building programs from source code stored in a CVS repository. The build system is made up of two basic subsystems. The first ("build") calculates the dependencies of a target, retrieves the source code, and runs commands to build that source code in the correct order. The second component ("Umake") is a cross-platform Makefile generator, which generates makefiles that work with MSVC, CodeWarrior, and typical Unix toolchains. Umake can be used independently from the build program.
PalmFontConv is a collection of command-line utilities to manipulate Palm fonts in both v1 and v2 formats. Currently, there is a converter that converts between afnx, nfnt (low, high, or both densities), NFNT, and text editable formats, and another converter that converts Type 1/TrueType/BDF/PCF and other formats supported by FreeType2 into the text editable format, code for generating Plucker and PalmBible+ compatible anti-aliased fonts. There are also a bunch of GUI shells for generating font packages for Plucker, PalmBible+, Fonts4OS5, and FontSubst.