We have many users who use our OpenOffice plug-in to easily edit and save their files to/from OpenOffice. This is solution is fairly transparent to the end user as the plug-in installs itself as a toolbar option and is very easy to use. There are numerous blog posts outlining how this can be done. As OpenOffice has a plug-ins site the plug-in is fairly easy to find and download and has a reasonable amount of visibility.
What you may not know is that we also have the same plug-in available for Microsoft Office. This also install itself as a Toolbar plug-in and makes editing and saving files / to-from Google Docs just as transparent as its OpenOffice cousin ! The toolbar is free to download, and a Google Docs account is free to register.  The short video below shows how the easy the solution is to work with.