GNU GRUB is a Multiboot loader. It was derived from GRUB. It is an attempt to produce a bootloader for IBM PC-compatible machines that has both the capability to be friendly to beginning or otherwise non-technically interested users and the flexibility to help experts in diverse environments. It is compatible with FreeBSD, NetBSD, OpenBSD and Linux. It supports Windows 9x/NT/2000/XP and OS/2 via chain-loaders. It has a menu interface and a command-line interface.
TransFig is a set of tools for creating TeX documents with graphics which are portable, in the sense that they can be printed in a wide variety of environments. The fig2dev program that is part of TransFig is used by xfig when exporting drawings to the various output formats such as PostScript (and EPS), CGM, JPEG, LaTeX, PNG, and more.
Mup produces very high quality PostScript printed music or a MIDI file from a text input file. It can handle almost any kind of music, instrumental or vocal, including tablature, shaped notes, guitar grids, alternate tunings, user-defined symbols, and much more. Mup has been under active development since 1992.
Ilib is an image manipulation library for developers. It's capable of reading and writing images (PPM/PGM, PNG, JPEG, GIF, XPM, BMP) and many drawing functions including drawing lines and text using any BDF (X11) font. It's great for generating GIFs/PNGs from a CGI or generating graphs. Ilib includes sample applications for generating graphs for HTTP access.log files and QuakeWorld server frag log files and a tool for creating image indices from a group of images.
Data::Locations is a virtual file manager which allows you to write and read data (text and binary) to and from virtual files (think of bubbles). Moreover, this manager allows you to (recursively) define "magic" insertion points in these virtual files (bubbles inside other bubbles) which can be filled in (inflated) later (through a "straw", i.e., the object's reference), at any convenient time and in any order you like. Since this software acts purely in memory, there is no slowing down through costly file input/output (i.e., no temporary files).