I often advise downloading the free OpenOffice.org desktop suite to fully replace MS-Office (why should you pay for a Microsoft product that is leading you to spending more and more to get a suite that is more and more difficult and incompatible with time? Just dump Word and Excel for a better solution).
But, a found another option for free MS-Word: ABI Word is an open source word processor available for quite some time, but the latest version (v2.6.5) is now compatible with all the meaningful file formats like MS-Word 2007 and OpenOffice.org Writer. These XML-based file formats are usable in this freely downloadable word processor.
I do not use it by myself, but it looks good enough to check it if you want a pretty neat word processor solution to replace your MS-Word for free.