According to a post on Boing Boing, Steve Aftergood of the Federation of American Scientists (FAS) has posted the US National Security Agency's guide to sanitizing Word and PDF documents.
With high-profile PDF censorship gaffes in the last few years due to misunderstandings about the technology, this PDF guide produced by the NSA cites common information leakages and includes a step-by-step guide on the censorship of Word documents and the subsequent conversion to PDF.