Google PDF/PPT Viewer

You can use google view to show PDF files on the next. You don't have to upload the files to google docs but the pdf file should be available online.

Direct URL Method:

http://docs.google.com/gview?url=http://yourdomainname.com/yourfile.pdf

Direct URL with Embedded:

http://docs.google.com/gview?url=http://yourdomainname.com/yourfile.pdf&embedded=true

IFrame method:

You can us both PDF and PPT files.