Magsformiles is offering the Economist 1 year digital and 1 year print subscription for the following miles:

Alaska Airlines miles: 2,100 miles for 1 year digital, 3,900 miles for 1 year print.
American Airlines miles: 1,800 for 1 year digital, 3,200 miles for 1 year print.
Delta Skymiles:1,800 miles for 1 year digital subscription, 3,200 miles for 1 year print.
Frontier Airlines: 2,100 miles for 1 year digital, 3,900 miles for 1 year print.
Hawaiian Airlines: 2,100 miles for 1 year digital, 3,900 miles for 1 year print.
Spirit Airlines: 2,600 miles for 1 year digital, 4,800 miles for 1 year print.
United Airlines miles: 1,800 miles for 1 year digital subscription, 3,200 miles for 1 year print.
US Airways Dividend Miles: 1,800 miles for 1 year digital subscription, 3,200 miles for 1 year print.

This is a great way to use orphan miles towards a subscription. They also have other magazines available as well at the above links. The fine print says new subscribers only, though in my experience I’ve been able to get it anyways, just not as a renewal to a current subscription.