Eric Garcetti · CC BY 2.0

Hired by Bill Gates in 1980, he rose to lead Microsoft as CEO from 2000 to 2014, a stretch in which the company tripled sales and doubled profits even as it ceded ground to Apple and Google during the mobile era that redefined the industry. He has since built the Ballmer Group as a philanthropic investment vehicle and owns the Los Angeles Clippers, whom he bought in 2014 after the NBA forced out the team's previous owner over racist remarks.