Just found this "new" feature from Gmail this morning:
# View as HTML
Now you can view Microsoft Office, OpenOffice or .pdf attachments as web pages by clicking the "View as HTML" link instead of downloading. For when you want to see it faster, you're on a mobile device, or you don't want to install software just to view a document. Learn more
I like this feature! Compared with displaying an word/xls/pdf... icon next to the document name when viewing an email, create a HTML view of the document make more sense, especially for those large attachment. The tables and images are lost when viewing a PDF file in my example this morning, but well, it's so far so good and acceptable. (Hmmm... how can they do that... the technology behind and performance are pretty good!)