Co-founder and CEO, Google
Since the co-founder returned to the CEO role last year, he's been bent on proving Google still has its mojo, even as he puts his own stamp on the search engine he co-founded 14 years ago. Straight out of the gate, Page closed Google's boldest acquisition to date—the $12.5 billion purchase of Motorola. He also stripped away layers of management and shuttered dead-end projects. Google+, its self-styled "social spine," hasn't exactly been a home run—as of last count, its 100 million active users are a drop in the bucket compared with Facebook's 1 billion. Still, Google pretty much owns the mobile ad space, pulling in north of 95% of all dollars spent on phone ads. And its Android operating system has been a runaway success. (It powers over half of all smartphones sold in the U.S.) For their part, shareholders have already voted: Google's stock is at an all-time high. This year Page leapfrogs Mark Zuckerberg to take the No. 1 slot on our list for the first time.
Out of this world: Page recently invested in an asteroid mining venture called Planetary Resources, which aims to "expand Earth's natural resource base." -- Michal Lev-Ram
Editors' Note: A previous version of this story incorrectly stated that Google+ had 100,000 active users. The number is actually 100 million. Fortune regrets the error.
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