Even when disabled, the 'People Widget' takes up a column space of 220px width at the right, which is very valuable screen real estate.
If you don't use, don't like the people widget, and want the space back, use this.

Notes: it may hide other stuff such as ads to the right ;), and create a horizontal bar at the bottom.
It was made for people who use the reading pane Labs feature, it may not work without it.