A little belated something for World Water Day (yesterday): National Geographic has released a special issue that delves into the challenges facing our most essential natural resource. "Water: Our Thirsty World" will be soon available at newsstands everywhere. But, right now, you can now download a free interactive version that includes all of the print magazine content, plus lots of extra online goodies. The free download requires registration and is available only until April 2.
A great find by Maria Popova aka @brainpicker