Nessus security checker
Nessus security checker
http://www.nessus.org/download.html
MRTG
MRTG
http://www.mrtg.org/
Cockpit file manager
The unix cockpit 3.0 is a nifty open source file manager for x11/unix and runs under almost any unix flavour.
http://www.klagges.com/uc.html
Bigbrother monitoring
Big brother systems and network monitor
http://www.bb4.org/
OpenSSH
The main openssh page
http://www.openssh.org/
OpenSSL
OpenSSL
http://www.openssl.org/
VIM editor
VIM editor
http://www.vim.org/
Sourceforge
The world's largest development and download repository of open source code and applications
http://sourceforge.net/
Snort
The open source snort intrusion detection and prevention system is the most
flexible and widely deployed solution available.
http://www.snort.org/
PGP
PGP
http://web.mit.edu/network/pgp.html
VNC
The only professionally supported versions of vnc. latest and best free and commercial versions available, over 100 million downloads.
http://www.realvnc.com/