QuickIndeqs allows users to specify a list of keywords or phrases which need to be indexing within a PDF file. The list of keywords is re-created listing each Keyword with the location (page numbers) separated by commas.
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.