PDF Annotator

PDF Annotator: "Previously, annotating, commenting or proofreading a document received for review in PDF file format was possible only by using multiple software products in a row—or only by printing the document and adding comments manually. With PDF Annotator, annotations can also be added in a natural way—using a pen—but everything remains in digital format. PDF Annotator allows commenting of PDF files in a single step."—Grahl Software Design

This is the missing piece for many electronic forms applications. Nice!