Apache Lenya is an Open Source Java/XML Content Management System and comes with revision control, multi-site management, scheduling, search, WYSIWYG editors, and workflow.

You can move, copy, rename, archive or delete individual pages or whole parts of your site with an easy to use site view that [...]

SlimStat is an open source web analytics application that collects & presents statistics information about your website.
It is built with PHP-MySQL & can be integrated into websites with JavaScript (like Google Analytics) or PHP.

For  the given period, the application can display:

the number of visitors/pageviews
referrer URLs, domains
search terms
browsers, OSs, countries, screen sizes

OTRS is an open source trouble ticket system for easily managing support requests in a multi-agent interface.
The application can auto-convert e-mails into tickets (e-mail piping) which “eliminates the need of using the web interface” for customers.

OTRS is used by large organizations like Opera, MySQL AB, BitDefender, Suse & has very nice features like:

transfer of tickets [...]

Project Management is often defined as the science of organizing, planning and managing the available resources of a particular organization to successfully complete a project, which aims to meet the organization’s goals and objectives. This type of system will be useful in ensuring the timely and effective output of a project. Furthermore, the implementation of [...]

Symphony is a XSLT-powered open source CMS that is created with PHP & uses MySQL for storing data.
It offers a very flexible usage as the data, logic & templating layers are all independent, meaning that whatever you implement can be modified, added or removed with minimum effort.

When compared to other popular CMS applications, the biggest [...]

rsslounge is an open source, full-featured & web-based RSS feed reader application that is built with PHP-MySQL.
It allows you to read your feeds, categorize or filter them, set priorities & more from an Ajax-based slick interface.

Besides the standard feed items, rsslounge supports images & photoblogs.
For periodically fetching content from feeds, it offers 2 options: cron [...]