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.
|McDonald's gives Charles Ramsey free food for a year|
|4 federal agencies to shut Friday|
|Obamacare premiums in California lower than predicted|
|Japan stocks rebound after big plunge|
|Bitcoin more powerful than fastest supercomputers|