With a table model in place we can introduce direct manipulation interfaces to work with structured data. In the demo below, we create a new computed column and further aggregate it into a summary row below using just drag-and-drop.
prabros.com/bean/design#...
The table model Bean uses enables representing complex tables easy and natural to work with. You can use a query language that can zero-in on any of the intersections of areas marked by the labels and run aggregates, filters and other functions over it.