Open online resources with Google Drive Viewer. Supports various formats including DOC, XLS, PDF, PPT, ZIP, HTML, TXT, JS etc.
Supports Word, Excel, PowerPoint, PDF, ZIP and more formats. File should be online and publicly accessible. Opened files can be easily saved to the Google Drive. Doesn't work on ***Google Search Result Pages***.
List of supported file types: https://support.google.com/drive/answer/2423485?hl=en&p=docs_viewer&rd=1
Test extension on this page: http://browsernative.com/test/drive.php
Not affiliated with Google.