DocJax is a search engine for documents. It is well-designed and it provides relevant results, I think this is useful to add the site in your bookmarks. Click on the picture below to go to DocJax!
It allows you to search documents and e-books from everywhere. DocJax supports .pdf (Acrobat Reader), .xls (Ms Excel), .doc (Ms Word) and .ppt (Ms PowerPoint) file formats in search results.
You can filter results based on these formats. You can also preview a document before deciding to download it.
DocJax is in beta, thus we hope some improvements. For example, OpenOffice documents are not supported and a language filter is not available…