As a Scrum Master putting together data for the Sprint Review, I want to be able to show a burndown that shows the burndown of initial scope along with the burndown of scope creep, so that when my team finishes everything they committed to at the start of the Sprint and they Bring more work in, it communicates that we've not only met our Sprint Commitments but met them.

The chart then would show the idealized line and then the burndown of the work that was present at the start of the Sprint. When Items are brought into the Sprint, instead of a single burndown line going up, it branches and moves upward (this line would track the increase/completion of items outside of the scope of the Sprint commitment). If all outside of scope items are finished, the line merges with the burndown and goes away.