Online collaboration service with file viewer supporting various document formats, including ODF;

Dio is a native PHP simple OpenDocument generator. Unlike OpenDocumentPHP project, it has been design with PHP PEAR/Zend_Framework convention, not Java.

Docbook2odf is a toolkit for converting DocBook to ODF using XSLT.

Dokuwiki is an open source Wiki written in PHP. A free ODT plug-in is available, allowing users to export a wiki page to OpenDocument Text.

This Drupal module allows one to import ODF files into the popular WebCMS. Currently only the content of ODF text documents (.odt) is imported, future releases will support other ODF types as well as importing styles.

EuroOffice is the name of a free and open-source OpenOffice.org derivative and a set of accompanying free and non-free extensions. Most of the extensions also work with "vanilla" OpenOffice.org.

The EuroOffice application suite provides us a means to enable some of our extensions to do more than what is possible in OpenOffice.org. Since it is open-source we hope that these additions will be considered improvements by our users and adopted in the future by OpenOffice.org developers. We have signed the JCA, so nothing stands in the way of adoption.

ezComponents is a general purpose PHP components library. Starting with v2009.2, ezComponents Document supports reading, converting and writing ODF text files (.odt)

FileAid is a file manager and file viewer for Apple iPod Touch and iPhone. Version 1.3 now supports viewing of ODF documents, presentations and spreadsheets.

The Gnumeric spreadsheet is part of the GNOME desktop environment.

The goal of Gnumeric is to be the best possible spreadsheet without attempting to clone existing applications. Gnumeric can read and write ODF spreadsheets (.ods)

Google Docs & Spreadsheets accepts most popular file formats, including DOC, XLS, ODF, ODS, RTF, CSV, etc.