Why Microsoft's .docx Format is a Good Thing
http://www.guardian.co.uk/technology/2007/jun/21/comment.comment1

Schofield, Jack
Guardian Unlimited, The
2007

Abstract:

Here's a simple way to read one of the new Microsoft file formats, even if you have no Microsoft software installed. Let's suppose you have a file that ends with .docx, from the latest version of Microsoft Word. It's actually a zip file, so add .zip to the end and unzip it. You'll find a cluster of files and folders inside, and the one you want should be called document.xml. Double-click that and it will load in a browser window, where you can read the text.