PDF Search Tool helps you find PDF files by content
When I think about searching online, my first and often only thought is, "how can I do this with Google?" Well, Google's great at search, but that doesn't mean it's the best tool in every situation. Consider searching for PDFs containing specific information; wouldn't you like to see a nice clean list of PDF titles with links both to the PDF in question and an HTML version of it? PDF Search Tool offers exactly that functionality.
To be fair, Google can do this too, particularly if you use the search argument "filteype=pdf", but PDF Search Tool feels somehow more purpose-built. For those that are inclined, it's interesting to see what happens when you search for a well-known author's name; PDF Search Tool almost feels like a pirate ebook finder when used that way. Not that you would. Or should.