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|
|Bitcoin more powerful than fastest supercomputers|
|Japan stocks rebound after big plunge|
|Mailbox comes to the iPad|
|Obamacare premiums in California lower than predicted|