Cfengine is a tool for setting up and maintaining BSD and System-5-like operating system optionally attached to a TCP/IP network. You can think of cfengine as a very high level language, much higher level than Perl or shell: a single statement can result in many hundreds of operations being performed on multiple hosts. Cfengine is good at performing a lot of common system administration tasks, and allows you to build on its strengths with your own scripts.
E-MailRelay is a simple SMTP store-and-forward mail transport agent (MTA). It runs as an SMTP server, storing incoming e-mail in a local spool directory, and then forwarding the stored messages to a downstream SMTP server on request. It can also run as a proxy server, forwarding (and optionally pre-processing) incoming e-mail as soon as it is received. It does not do any message routing other than to a local postmaster. Because of its simplicity E-MailRelay is extremely easy to configure, typically requiring only the address of the downstream SMTP server to be put on the commandline.
Eric is a full featured Python and Ruby editor and IDE, written in Python. It is based on the cross platform Qt GUI toolkit, integrating the highly flexible Scintilla editor control. It is designed to be usable as an everyday quick and dirty editor as well as being usable as a professional project management tool, integrating many advanced features that Python offers the professional coder. Eric includes a plug-in system, which allows easy extension of the IDE functionality with plug-ins downloadable from the net. Current stable versions are Eric4 based on Qt4 and Python 2 and Eric5 based on Python 3 and Qt4.
GNU Make examines the timestamps on a set of interdependent files, and, if necessary, issues commands to bring them up-to-date. The user creates a makefile describing the files, their relationships, and the commands to run. Most often make is used to rebuild libraries and programs when their sources are changed, but it can be used for any situation where one set of files needs to be generated from another set.
Ghostscript is a processor for PostScript and PDF files. It can rasterize these files to a wide variety of printers, devices for screen preview, and image file formats. Since applications tend to prepare pages for printing in a high-level format such as PostScript, most Unix users with low-level bitmap printers, such as inkjets, use GhostScript as part of the printing process. In addition, Ghostscript is capable of converting PostScript files, functionality comparable to Adobe Acrobat Distiller, but on the command line. In addition, Ghostscript is used for file import and viewing by a great many other applications, including xv, ImageMagick, gimp, and xdvi. Several GUI wrappers for viewing PostScript and PDF files exist, including GSview, ghostview, gv, ggv, and kghostview. This is far from a comprehensive list.
Highlight is a universal converter from source code to HTML, XHTML, RTF, TeX, LaTeX, SVG, BBCode, and terminal escape sequences. (X)HTML and SVG output are formatted by Cascading Style Sheets. It supports more than 170 programming languages, and includes 80 highlighting color themes. The configuration files are Lua scripts with plug-in support. The converter includes some features to provide a consistent layout of the output code.