Many of us use OpenOffice.org as a fantastic, free alternative to MS Office, because it offers compatibility, with MS Office products. I've recently started using an extension for it that makes it even more attractive to use OpenOffice.org.
'OpenOffice.org2GoogleDocs' allows one to export and import documents to Google Docs, Zoho, and WebDAV. I use it to sync my Google Docs, to my local drive. I can then edit them, off-line, and then sync the docs back up to my Google Docs. Google Docs itself uses the open ODT format, so there is no translation needed. However, because OpenOffice.org can read and write DOC files, translation is not an issue anyway.
I discovered this extension because a friend of mine was looking for a way to sync her Google Docs, to her netbook, for times when WiFi was not available. Thanks, Cindy, for taking me down this research road!
You can find OpenOffice.org, available for download for LINUX, Windows, and Mac, here: http://download.openoffice.org/index.html
Look here for the extension: http://extensions.services.openoffice.org/project/ooo2gd