From Google Chrome Blog: Chrome Beta on Windows and Mac can now open Microsoft Word, Excel, and PowerPoint files directly in the Chrome browser. Just install the Chrome Office Viewer (Beta) extension, then clicking a link to an Office file will open it directly in Chrome. The Chrome Office Viewer also offers protection from malware delivered via Office files. A specialized sandbox is used to impede attackers who use compromised Office files to try to steal private information or monitor your activities.