More than any other star around, Ashton Kutcher grasps the ways in which emerging technologies are reshaping our lives. He's become an in-demand guru for his insights into social media and the future of the Internet, evangelizing about paradigm-busting new brands like the location-based networking service Foursquare, the cutting-edge travel-bookings site Hipmunk, and the user-curated product platform Fancy. And as an investor, he puts his money where his mouth is, too, backing many of the companies he champions here, both on his own and with A Grade Investments, which he founded with Maverick Records' Guy Oseary and the supermarket billionaire Ron Burkle. Consider this his guided tour of all the cool stuff happening online right now.

Details: Most people know you as an actor. How'd you become such a tech nerd?
Ashton Kutcher: After Punk'd, my company Katalyst did a deal with AOL to produce short-form content for the Web. At that time it was a different game. If you got front-page coverage on any popular website, you could probably get a push. But about three years ago I started playing around with Facebook and Twitter, and I realized what could be done inside real-time shared media, where you didn't have to be connected to a big portal or big media outlet to get your story out. I thought that was pretty powerful.

Details: The line between online life and real life is getting blurrier. Is that a good thing?
Ashton Kutcher: I wouldn't bifurcate the two. I wouldn't say you have an online life and a real life. I think technology is just mapping and organizing what already exists. If you're an asshole offline, you're probably an asshole online.

Details: As a celebrity, you're used to managing the boundary between your public and private selves. Is that something we all have to do now?
Ashton Kutcher: You have to learn to negotiate it, or you can choose not to participate. It's almost like a manifestation of God. People used to behave morally because they thought God was always watching—in some ways God today is the collective, and the collective is watching.

Details: Sounds kind of creepy. Do you think privacy is overrated?
Ashton Kutcher: I think privacy is valuable. You don't have to share everything, and it's healthy to occasionally hit the pause button and ask yourself if you're oversharing. But at the end of the day, if you're not doing anything wrong you don't have anything to hide.

Details: For a while your Twitter account was the most popular in the world, and you're still in the top 10. What's your secret?
Ashton Kutcher: A lot of people use social media to share mundane things or for self-glorification. I try to use it to share interesting things with people. Tony Hsieh, who created Zappos.com, said to me, "Everything I post on the Web has to be ICEE"—it has to inspire, connect, entertain, or educate. The other important thing about social media is that it's not about what you post but what you listen to. It's about sharing the valuable ideas that you hear. You don't want to be the source of everything, you want to be the pipe for everything.

Details: What do you think is coming that will blow our minds five or ten years from now?
Ashton Kutcher: I think the big next wave will be wearable technologies. Your phone will be your true PC, and these technologies will act as your mouse and keyboard. You'll have a high-fashion bracelet that will perform functions for you—it'll track your health, your movement, your sleep, your activity—and by wearing a couple of rings, you'll be able to type in the air or take pictures with your fingers. There'll be a device that will track your eye movement, whether it's an earpiece with a camera or a necklace that can project and record. That Tom Cruise movie, Minority Report, got a lot of it right from what I've seen.

Details: You consult with a lot of the tech companies you invest in. If Mark Zuckerberg asked you for advice, what would you tell him?
Ashton Kutcher: I'd ask him a lot of questions rather than tell him anything. That's generally how I enter the room with all of these guys.

Details: There's chatter about Facebook hitting a plateau. Is it in any danger of going the way of Myspace?
Ashton Kutcher: I actually think Twitter has a greater danger of becoming Myspace-y. Myspace was this open platform, and Twitter has the same dynamic: You can have millions of people within your social network, so it goes outside your weak-tie relationships. There's a danger of it becoming spammy, and that's what really hurt Myspace. There was more noise than signal. I have people hit my @reply feed every day with garbage, and if Twitter doesn't apply the proper filters, it'll be harder to find the information you want. With Facebook, I'm probably not going to get spammed from my aunt or my best friend.

Details: Your aunt might spam you with cat photos.
Ashton Kutcher: That's right. And that's okay.

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