The latest beta version of Google Chrome now allows you to open Office files (documents) directly in the browser. Windows users and Mac users can now view a Word, Excel or Powerpoint files directly from Google Chrome.
The only requirement is to install the "Chrome Office Viewer" extension.
This extension is experimental, as recalled by Google Chrome browser developpers on the official blog.
Note that: "Chrome Office Viewer" allows you to view documents, but not to edit them.