Grid, Board & Gallery — Totals at the foot of a column

Summarise in the toolbar (or any column's own menu) puts an aggregate in a row pinned to the bottom of the grid. Numbers offer sum, average, min, max and median; dates offer earliest and latest; checkboxes offer checked, unchecked and % checked; and every field type offers filled, empty, % filled, % empty and unique values. The figure is worked out by the database over every row the view matches, not over the rows currently loaded — which is the point of having it, and the reason it doesn't climb as you scroll further down. When the grid is grouped, each group carries its own totals in its header rather than in a row underneath, so they stay readable when the group is collapsed — which is where a group total earns its keep.