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.
Gollem is a Web-based file manager that provides the ability to fully manage a hierarchical file system stored in a variety of backends such as a SQL database, as part of a real filesystem, or on FTP, Samba or SSH servers. It supports uploading and downloading of files, basic file operations, permissions support, and MIME recognition and viewing of files through the Horde MIME library. It is fully internationalized and translatable.
MIMP is a version of the popular webmail client IMP intended for mobile phones and PDAs. Basic webmail functionality is implemented, including mailbox viewing and paging, viewing messages, deleting, replying, forwarding, and composing new messages. It utilizes the Horde Application Framework.
MuseScore lets you notate and compose music easily with your keyboard, your mouse, or a MIDI keyboard. You can print beautifully engraved sheet music or export it as PDF or PNG. You can play your score, transpose it, and save it as audio or MIDI file. MuseScore also supports MusicXML to let you share your composition with other scorewriters. MuseScore is often advertised as a cost effective alternative for Sibelius and Finale.
Pootle is a Web-based translation and translation management tool. It provides a rich set of features for mangaging a translation project. It integrates components of the Translate Toolkit to provide error checkers for translation messages and the ability to download files in a number of formats: PO, XLIFF, CSV. Pootle can also provide compiled PO files for download. You can use it to assign work to translators in your team, and you can define goals to help focus the efforts of your translation. Pootle can run without a Web server or be proxied through your existing Apache server.
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.