Quick Database Manager

https://dbmx.net/qdbm/

Qhull computes convex hulls, Delaunay triangulations, and halfspaces

http://www.qhull.org

The build utility of the Qt project

http://www.trolltech.com/products/qt/index.html

A command line program to query game servers on the net

http://www.qstat.org/

Qt Documentation

http://qt.nokia.com/products/qt/index.html

Quake III Arena data files

http://www.idsoftware.com/games/quake/quake3-arena/

Test performance of storage devices

Randr extension headers

https://www.freedesktop.org/wiki/Software/xlibs/

RDF Parser Toolkit for Redland

http://librdf.org/raptor/

RDF Parser Toolkit for Redland

https://librdf.org/raptor/

Distributed, collaborative, spam detection and filtering network

http://razor.sourceforge.net/

Unix incarnation of the plan9 shell

https://github.com/rakitzis/rc

Version control system (as was in FreeBSD prior to removal)

https://www.gnu.org/software/rcs/

Lexer generator for C, C++ and Go with a focus on generating fast code

https://re2c.org/

Library for editing command lines as they are typed

https://tiswww.case.edu/php/chet/readline/rltop.html

Converts files between character sets and usages

https://www.gnu.org/software/recode/recode.html

RECORD extension headers

http://www.freedesktop.org/wiki/Software/xlibs

RenderProto protocol headers

https://www.freedesktop.org/wiki/Software/xlibs/

Resource extension headers

https://www.freedesktop.org/wiki/Software/xlibs/

A fast redirector and access controller for squid

http://www.bsdnexus.com/retsina/index.htm

Convert .rpm files to cpio format

Restricted Secure SHell only for sftp or/and scp

http://www.pizzashack.org/rssh/index.shtml

Network file distribution/synchronization utility

https://rsync.samba.org/

Ruby interface to Oracle Berkeley DB revision 2 or later

https://github.com/knu/ruby-bdb

Ruby interface to Berkeley DB revision 1.8x with full feature support

http://moulon.inra.fr/ruby/bdb1.html

Ruby tool for converting wiki-like markup

http://deplate.sourceforge.net

Binary data dumper module for Ruby

http://www.geocities.co.jp/SiliconValley-Oakland/2986/

An object-oriented interpreted scripting language

http://www.ruby-lang.org/en/

nsupdate utility with the GSS-TSIG support

https://www.isc.org/software/bind

Scan_ffs recovers lost disklabel

ANSI C version of the SciMark2 benchmark

https://math.nist.gov/scimark2/download_c.html

Converts the output of "vidcontrol -p" to text

Multi-screen window manager

https://www.gnu.org/software/screen/

Small and lightweight screen(1) wrapper

https://sourceforge.net/projects/screenie/

ScrnSaver extension headers

http://www.freedesktop.org/wiki/Software/xlibs

"Simplified" DocBook XML DTD

https://www.oasis-open.org/docbook/xml/simple/

A utility for generating secure passphrases

http://www.core-dump.com.hr/?q=node/28

Extensive german HTML reference

http://www.selfhtml.org/

Set of utilities that send SCSI commands to devices

http://sg.danny.cz/sg/sg3_utils.html

Generates groff and HTML from linuxdoc and docbook SGML documents

Interoperability between desktops and collaborative environments

http://oscaf.sourceforge.net

Generic script compiler

https://github.com/neurobin/shc/

HTTP regression testing and benchmarking utility

https://www.joedog.org/JoeDog/Sieg

Small (150k), fast, perl-based IRC client

http://www.iagora.com/~espel/sirc.html

SixXS IPv6 TIC+ tunnel broker heartbeat client

http://www.sixxs.net/tools/aiccu/

Fully automated, active web application security reconnaissance tool

http://code.google.com/p/skipfish

SIP scanner and identifier

http://www.wormulon.net/

S.M.A.R.T. disk monitoring tools

https://www.smartmontools.org

Samba-LDAP management and support tools

https://gna.org/projects/smbldap-tools/

Fast compressor/decompressor library

https://google.github.io/snappy/