Advantask for Google Docs is an extension that allows you to create tasks directly from a Document.

Utilizing the add-on a panel will be shown on the right side of your document, where you will be able to see your workgroups and create new tasks.

You can use Advantask for Spreadsheets for:
Follow on your work in progress documents
Create tasks related to a specifications document.
Deaggregate items of a task in a document
Create functional definitions (software) and follow on the work in progress.
Create approval workflows for Social Media Publications
Edit documents associated to in-progress tasks.