In addition to Fortune's 40 Under 40 list, we're also keeping our eye on these 20 innovators, young guns from a wide range of industries and backgrounds.
|China to fight pollution with drones|
|The medical marijuana ad that never aired, despite contrary media headlines|
|2 million students missing out on college aid|
|Boeing reports wing cracks on Dreamliners|
|Bitcoin matters. Ignore the media circus.|