PostStrip is a PDF work-flow tool that provides seamless tracking of a publication, indicating which parts are missing and which are present, then pre-flighting them to ensure they image correctly. In short it provides discipline to a process and, because PostStrip always knows about every element in an edition, it brings a new standard to the table for monitoring the publishing process.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.