Enzyme is an architecture for creating user-searching-user applications. Right now, it is primarily useful as a resume create/search and HR management system. However, it's potential uses are wide-ranging, and it offers PHP developers an alternative to relying on simple "keyword" searching systems.
LinPHA is an easy-to-use, multilingual, flexible photo/image archive/album/gallery written in PHP. It uses an SQL database (MySQL/PostgreSQL/SQLite) to store information about your pictures. It comes with an HTML-based installer, so you don't need experience in setting up SQL databases. Thumbnails are created as needed and stored in the SQL DB. It features complete user management, top ten statistics, hidden albums, different themes, slideshow, filemanager, uploader, watermarks, benchmark, printing, and more.
PHPX is a Web portal system, blog, Content Management System (CMS), forum, and more. It is designed to allow everyone to be able to have feature-rich, interactive websites even if you do not know a bit of programming. Some key features include fully-integrated forums, downloads, an image gallery with slideshow and auto-thumbnailing, support ticket system, a GUI interface for Web page content management, news with topics and instances, and a whole lot more. It allows you to fully customize the look of your site.
TYPO3 CMS is a Web Content Management System which features automatic creation of navigational menus, headlines, and other dynamic graphical elements, automatic conversion and scaling of images, the ability to present different templates based on variables such as client browser or country code, support for multiple templates on a site, and a built-in password-protection option. Pages can be timed to be shown on a certain date, be hidden on a certain date or just temporarily hidden. TYPO3 supports search in SQL-databases and redesigning of a website at once is just a matter of creating a single new template.
Urd is a Web-based Usenet binary download manager. It stores the newsgroup information in a MySQL database and aggregates the articles into sets of a single download (e.g. one album or movie). The Web interface can be used to search with regular expressions. It uses its own downloading daemon that has support for scheduling downloads and updating databases. URD can also download directly from NZB files and even create NZB files. Further features include custom scripts, multiple languages, a template based Web interface, support for multiple servers, automatic par2 and unrar support, and an intuitive user interface.