Google Docs has an undocumented feature that lets you embed online PDF files and PowerPoint presentations in a web page from anywhere on the web. Zoho Viewer, and PdfMeNot offers similar features.

Here's the code:

<iframe style="WIDTH: 600px; HEIGHT: 500px" src="http://docs.google.com/gview?url=http://infolab.stanford.edu/pub/papers/google.pdf&amp;embedded=true" frameBorder=0></iframe>

Note: Replace bold in the code with your PDF and PPT files URL.