DBPrism is an open source framework to generate dynamic XML from a database. It connects Oracle databases with Apache Cocoon, providing a high performance DBGenerator with functionality such as parallel content aggregation and ESI cache protocol. It also includes a powerlful database oriented CMS built on top of Apache Cocoon2 and DBPrism.
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.
QSD is a *nix daemon for administering game servers (like Quake, Half Life, etc). It uses a flexible plugin architecture for both authentication and for interfacing with the individual game servers. QSD has been designed from the ground up to relieve many problems game server admins deal with from day to day.
Tof is a Web-based photo album. It is based on slooze, and additionally has viewing rights, picture rating and sorting by rate, indexing with keywords, picture upload through the Web, thumbnail creation, and multiple languages support. It is being developed with PostgreSQL, but should be easy to port to MySQL thanks to phplib.
dbMan is a complex SQL monitor for common database systems (PgSQL, Oracle, MySQL etc.). It's based on Perl and DBI interfaces. Features include a command history buffer, tab completion, editing Oracle objects, simultaneous connections, SQL help, importing and exporting of tables, Oracle explain plan, and more. dbMan is made as a simple kernel and many extension modules, and you can make your modules with a simple HOWTO.
XMLDB uses an RDBMS to persist arbitrary XML documents. Due to its storage mechanism, searching for and recalling documents is extremely quick. You can also perform XSL translation on documents with surprising speed. The library can be used in any program to store libxml2 documents. A PHP module is also included, making XMLDB into a complete three-tier Web application development suite.