There is room for four runways, with a tiny fraction of the impact at Heathrow.

ECONOMIST: Letters

For instance, product-service systems like car sharing and tool libraries--in which a product we used to buy and take home becomes a service we use only as needed--offer us access to the products we want at a fraction of the ecological impact.

FORBES: Magazine Article

And if some substantial fraction of them do, how much overall impact does this have on the aggregate test scores of the lottery-losing children?

FORBES: KIPP and the Charter School Lottery