AbiWord is a free word processing program similar to MS Word.
OpenOffice.org Office Suite
Wordprocessor, SpreadSheet, Database, Presentation, Illustration
Portable OpenOffice.org is a fully functional package of OpenOffice.org optimized for use on a USB key drive.
LibreOffice is a free and powerful office suite, and a successor to OpenOffice.org (commonly known as OpenOffice).
Portable LibreOffice is a fully functional package of LibreOffice optimized for use on a USB key drive.