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.
KAlarm lets you schedule personal messages to display, audio files to play, commands to execute, or emails to send. Among its options, it allows you to choose the message font and color, recurrence schedule, whether to display an advance reminder, whether to speak the message or play a sound when it is displayed, and whether to cancel the alarm if it can't be triggered on time (e.g. if you are logged out at the time). As well as using the graphical interface to configure alarms, you can use the command line, and there is a D-Bus/DCOP interface for other applications.
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.
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.
Horde Groupware is an enterprise ready browser-based collaboration suite. Users can manage and share calendars, contacts, tasks, and notes with the standards compliant components from the Horde Project. Horde Groupware bundles the separately available applications Kronolith, Turba, Nag, and Mnemo. It can be extended with any of the released Horde applications or the Horde modules that are still in development, like a file manager, a bookmark manager, a forum, or a wiki.