phpMyFAQ is a multilingual, completely database-driven FAQ system. It support various database systems and it also offers a content management system with a WYSIWYG editor, an image manager, flexible multi-group and multi-user support, a news system, user tracking, language modules, templates, PDF support, a backup system, Active Directory support, and an easy to use installation script.
phlyMail is a groupware, webmailer, and PIM. It offers unlimited nested groups, unlimited POP3/IMAP profiles, quotas, an integrated address book, a calendar with multiple reminders and event repetitions, a file manager with an integrated WebDAV server, the ability to send faxes, SMS support (which lets you send SMS, get reminded of events via SMS, and get email notification via SMS), a bookmark manager, themes, and multilingual support. It uses either sendmail or SMTP to send email, and can handle MIME and SSL connections. Support for IDN (Internationalized Domain Names) is included. Through its modular design, it's easy to add completely new features as modules, which can be plugged into the system.
Sablotron is an XML toolkit which implements XSLT, DOM, and XPath. Sablotron is written in C++, and it can be used from C, Perl, Python, PHP, ObjectPascal, and via a command line interface. It supports the XSLT 1.0, XPath 1.0, and DOM Level 2 W3C specifications. It is designed to be as compact and portable as possible, and is maintained as an Open Source project by Ginger Alliance.
SynchroEdit is a browser-based document editor for use by multiple users simultaneously. It is a form of same-time, different-place groupware. It allows multiple users to edit a single web-based document at the same time, and it continuously synchronizes all changes so that users always have the same version.