DocAppender is a Google Forms add on, or extension, that allows for the collection of information via a web form and then appending that information to an existing Google document. It was created by Andrew Stillman and the great folks at New Visions Cloud Lab.
The DocAppender web page outlines many possible uses, including using the form to add to a running record of classroom visitations. One way I would like to see teachers and students utilize it as a way to capture their weekly and daily journal entries using their Chromebooks. A nice way to capture all of their entries in one document.