OpenOffice.org  3.1.0 RC2
OpenOffice.org is the leading open-source office software suite for word processing, spreadsheets, presentations, graphics and databases. The application is available in many languages and works on all common computers.
OpenOffice.org is the result of over twenty years' software engineering. Designed from the start as a single piece of software, it has a consistency other products cannot match. A completely open development process means that anyone can report bugs, request new features, or enhance the software.
Easy to use
OpenOffice.org is easy to learn, and if you're already using another office software package, you'll take to OpenOffice.org straight away. The world-wide native-language community means that OpenOffice.org is probably available and supported in your own language.
Best of all, OpenOffice.org can be downloaded and used entirely free of any licence fees. OpenOffice.org is released under the LGPL licence. This means you may use it for any purpose - domestic, commercial, educational, public administration.
Note: As of April 2011, commercial development of OpenOffice.org project has been terminated. The code was contributed to the Apache Software Foundation, where volunteers continue to develop it. LibreOffice, a fork of OpenOffice is now available for download here.