New Gmail Lab Feature: PowerPoint and TIFF file viewing
Google has improved Gmail's attachement "viewer" again. Now you get better support for TIFF (Fax) and PowerPoint:
This viewer provides a richer set of features than the old "View as slideshow" version: you can zoom in and out, select text to copy and paste, and "print" the presentation to a PDF document. And, unlike the old version, we no longer require you to have a Flash plugin installed on your browser.