phpMyAdmin is a tool intended to handle the administration of MySQL over the Web. It can create, rename, and drop databases, create/drop/alter tables, delete/edit/add fields, execute any SQL statement, manage keys on fields, create dumps of tables and databases, export/import CSV data, and administrate one single database and multiple MySQL servers.
Thunderbird is a total redesign of the Mozilla mail component to produce a cross-platform, stand-alone mail application using the XUL user interface language. It has many new features, among them the ability to customize your toolbars the way you want them. a new look and feel with a large number of downloadable themes which alter the appearance of the client, and the ability to add UI extensions.
LimeSurvey (formerly PHPSurveyor) is a Web application that interacts with MySQL, MSSQL, or Postgres to develop surveys, publish surveys, and collect responses to surveys. Once a survey has been created, data can be inserted into the survey either by a "pretty" public screen which presents each question one at a time, or by a quick and nasty data entry screen. It includes the capacity to generate individualized "tokens", so that invitations can be issued to participants. It also has the capacity to set conditions on whether questions will display (branching), numerous question types, and a basic statistics function.
Kronolith is the Horde calendar application. It provides a stable and featureful individual calendar system with integrated collaboration and scheduling features. It makes extensive use of the Horde Framework to provide integration with other applications. It implements a solid, stand-alone calendar system, allowing repeating events, all-day events, custom fields, keywords, shared calendars, iCalendar support, generation of free/busy information, and managing multiple users through Horde Authentication.
AbiWord is a free word processing program similar to Microsoft Word. It is suitable for a wide variety of word processing tasks. It allows you to collaborate with multiple people on one document at the same time. It is tightly integrated with the AbiCollab.net Web service, which lets you store documents online, allows easy document sharing with your friends, and performs format conversions on the fly.
Roundcube Webmail is a browser-based, multilingual IMAP client with an application-like user interface. It provides the full functionality you expect from an email client, including MIME support, address book, and folder manipulation. High extensibility is granted by the plugin API and the user interface is fully skinnable using XHTML and CSS 2.