Having already recommended to the organisation I work for that we adopt SilverStripe to manage our intranet, I discover that, contrary to what I initially believed, searching binary documents (PDFs, DOCs) is not a feature in SS.
However, it is a key requirement of our intranet project.
I am sure that I can't be the first person with this requirement and that one of you clever fellas out there has had to crack this problem before. So, can anyone give me some advice?
Searching binary documents is not a common use-case for a website or CMS like SilverStripe. What you could use is the Lucene Search implementation of the Zend Framework: http://framework.zend.com/manual/en/zend.search.lucene.html
It's already able to index Office 2007 and HTML documents, and apparently [url=http://www.kapustabrothers.com/2008/01/20/indexing-pdf-documents-with-zend_search_lucene/]some people also successfully indexed PDF documents[/url] using the Zend Lucene implementation.
This doesn't stop you from using SilverStripe though. You should be able to include the needed parts of the Zend Framework and build wrapper functions in SilverStripe to fit your needs.