Helps you graph data in SEC filings.
When you visit a 10-Q or 10-K filing on sec.gov, the plugin will automatically create 'smart-links' on the left-hand side. The smart-link, if clicked, will take you to a graph of historical data.
For example, you can visit Barnes and Noble 10-Q filing, click on "Cash and Cash Equivalents" in the Balance Sheet, then see a graph of the data. You can see this process in the screenshots posted.