Embed-a-Cell is a Google Docs Add-on which allows you to embed the values of cells in Google Spreadsheets into your document.

The add-on also allows users to keep the values up-to-date in the document as they change in the underlying spreadsheets.

This can be a real time-saver when you are trying to prepare a summary report in the form of a document which is based on information stored in a spreadsheet. You can sprinkle values from your spreadsheet throughout your Google Document and then make changes to your spreadsheet without worrying about copying and pasting those values over and over again.