The original vi editor

http://ex-vi.sourceforge.net/

The traditional 4.4BSD /bin/csh C-shell

Resolution tool for Intel i915 video cards

Port of various original plan9 tools

http://tools.suckless.org/9base

Enhanced Printer Spooler

http://lprng.sourceforge.net/

High-performance CORBA ORB with support for the C language

Formats an ASCII file for printing on a postscript printer

http://www.inf.enst.fr/~demaille/a2ps/

Addressbook program with mutt mail client support

http://abook.sourceforge.net/

Program for sending email messages for CVS repository commits

http://search.cpan.org/dist/activitymail/

Adobe CMap collection

http://partners.adobe.com/asn/tech/type/ftechnotes.jsp

Database library for PHP

http://adodb.sourceforge.net

FTP-like shell for accessing Apple II disk images

Replacement and extension for Tripwire

https://aide.github.io/

Morse code training program

http://www.nongnu.org/aldo/

Interpreter for purely symbolic LISP

http://www.t3x.org/alisp/

Cross-platform library for games and multimedia programming

https://liballeg.org/

Mail and news client descended from Pine

https://www.washington.edu/alpine/

ALSA compatibility library

http://www.alsa-project.org/

ALSA compatibility library plugins

http://www.alsa-project.org/

Apache RealTime log stats

http://www.webta.org/projects/apachetop/

Program to list application's resources

Apache Portability Library

http://apr.apache.org/

Apache Portability Library

http://apr.apache.org/

Create & extract files from DOS .ARC files

http://arc.sourceforge.net/

Asynchronous DNS resolver library

ftp://athena-dist.mit.edu/pub/ATHENA/ares/

Open source implementation of the ARJ archiver

http://arj.sourceforge.net/

Text document format for writing short documents and man pages

http://asciidoc.org/

Afterstep clock with some language extensions

Spelling checker with better suggestion logic than ispell

http://aspell.net/

Aspell German dictionary

http://lisa.goe.net/~bjacke/igerman98/

Ispell compatibility script for aspell

http://aspell.sourceforge.net/

Programming reference for accessibility/at-spi

http://developer.gnome.org/projects/gap/

Programming reference for accessibility/atk

http://developer.gnome.org/projects/gap/

Software for collecting and analyzing calls from different PBX models

http://www.atslog.com/en/about/

Automatically configure source code on many Un*x platforms

http://www.gnu.org/software/autoconf/

Wrapper script for GNU autoconf

Automatically configure source code on many Un*x platforms (2.13)

http://sources.redhat.com/autoconf/

GNU Standards-compliant Makefile generator

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

Wrapper script for GNU automake

GNU Standards-compliant Makefile generator (legacy 1.4)

http://sources.redhat.com/automake/

Automatically restart SSH sessions and tunnels

https://www.harding.motd.ca/autossh/

Autotools meta-port

Tool to automatically update DNSSEC trust anchors

http://www.nlnetlabs.nl/projects/autotrust/

Free real-time logfile analyzer to get advanced web statistics

http://www.awstats.org

Dynamic pixel format conversion library

http://www.gegl.org/babl/

Network backup solution (client)

http://www.bacula.org/

Network backup solution (static client)

http://www.bacula.org/

Bacula document set

http://www.bacula.org/

Network backup solution (server)

http://www.bacula.org/

Interpreter for Snort unified2 binary output files

https://github.com/firnsy/barnyard2