OpenSource Apps for Linux

Self hosted Git management software
Download Link: https://github.com/gitlabhq/gitlabhq

WinSCP-(Free SFTP, SCP and FTP client for Windows)
Download Link: http://winscp.net/eng/index.php

PuTTY (the Telnet and SSH client itself)
Download Link: http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html

Nagios -(The Industry Standard In IT Infrastructure Monitoring)
Download Link: http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-3.5.0.tar.gz

Nagios Plugins
Download Link: http://prdownloads.sourceforge.net/sourceforge/nagiosplug/nagios-plugins-1.4.16.tar.gz

ImageMagick
Download Link: http://www.imagemagick.org/script/download.php

Fedora
Download Link: http://fedoraproject.org/en/get-fedora-options#formats

Ubuntu
Download Link: http://www.ubuntu.com/download

CentOS
Download Link: ftp://centos.arcticnetwork.ca/pub/centos/

ClearOS Community 6
Download Link: http://www.clearfoundation.com/Software/downloads.html

OpenVPN
Download Link: http://openvpn.net/index.php/open-source/downloads.html

Cacti
Download Link: http://www.cacti.net/download_cacti.php

Apache
Download Link: http://httpd.apache.org/download.cgi

Nginx
Download Link: http://nginx.org/en/download.html

Jenkins
Download Link: http://jenkins-ci.org/

MySQL
Download Link: http://dev.mysql.com/downloads/

PostgreSQL
Download Link: http://www.postgresql.org/download/