Behind the Scenes with Ashton Kutcher

Networking
"What he and Demi [Moore] do with Twitter is a good example," Combs writes. "Most people use it to promote themselves, but he uses Twitter to connect, to strike up conversations, to send positive messages to the millions of people who read his words." In 2009 Kutcher became the first Twitter user to reach 1 million followers.

• 2010 TIME 100
• Ashton Kutcher by Sean "Diddy" Combs