When Casey Neistat isn't behind a camera sharing his daily life with an online audience the size that Bill O'Reilly or Jimmy Kimmel attracts, you might find him ripping open boxes. Lots of boxes. Most of the time, he doesn't know what's in them when they arrive. It might be an assortment of bottled organic juices from the Midwest or a set of fancy headphones. It might be drone gear, or even a pair of live lobsters—butter included. (Neistat gets so many boxes that he has a second office just to handle the mail.) Companies large and small ship him goods hoping he might mention their wares to the 6 million people who subscribe to his YouTube channel.

"I have to admit, I've become pretty numb to it," he says, while opening yet another box inside his second-story office on the western edge of New York's Chinatown. "There's just so much stuff coming in."

There's one kind of package he's never numb to: fan mail. While YouTube stardom might seem like a niche kind of fame, over the past 18 months, Neistat's daily video blogs have gained him a massive following of 155 million people monthly. So far this year, his fans have seen him float in zero gravity, illegally wakeboard in a tuxedo through Amsterdam's canals, hang from a helicopter in Hollywood and snowboard through Times Square with a little help from the NYPD. (In 2010, The Hollywood Reporter likened Neistat and his brother, Van, "to film what Dr. Seuss is to literature.")

Neistat, Adweek's 2016 Digital Creator of the Year, has won not just the admiration of fans, but he's also won over the brands he's chosen to work with along the way. In one episode, he featured Nike's self-lacing Mag shoes and interviewed the engineers behind the long-awaited product inspired by Back to the Future. For the 2016 Academy Awards, he partnered with Samsung to document his trip to the Oscars using a Samsung Gear 360 camera. And this month Samsung released a video of Neistat teaching model Karlie Kloss how to shoot in 360 during New York Fashion Week.

"The challenge of YouTube for brands is that the creator model doesn't work for YouTube," Neistat explains. "Because people aren't subscribing to ideas or brands as much as they are to personality. It's personality-driven content. They identify with a person first and an idea second. If you try to replace that person with a brand, it's a much harder sell."

Even brands that don't pay Neistat can still benefit from his videos. In September, he received a free upgrade on an Emirates flight from New York to Dubai, which he turned into a nine-minute video of the trip (with a ticket value of $21,000) that's been viewed 25.5 million times.

"What's great about Casey is that he can weave in brand storytelling through an authentic point of view and tone of voice," explains a rep for Nike. "He loves what he does, he only works with brands he wants to work with, and it shows in his approach to the content he creates."

While other YouTube celebrities have found fame by doing something funny or by using some sort of visual effects, Neistat's films balance adventure and authenticity, and have inspired a generation of YouTubers.

He also comes from humble upbringings: After running away from home as a teenager, having a child with his then-girlfriend and living in a trailer park while washing dishes, Neistat maxed out his credit cards to buy an Apple computer so he could try his hand at video editing. (Clearly, that gamble paid off.) Years later, having amassed more than 1 billion views in the last 18 months, Neistat is ending his beloved vlog.

"I think it's time," he says. "When you know creatively that it's time to move on, it doesn't matter the cost; you have to move on. To give up 155 million views and millions of subscribers in one month is committing YouTube suicide, but I know that it's right. I know that I need to continue to challenge myself creatively—and I've grown far too comfortable in this medium."

He's also begun breaking out into creating his own tech. After finishing a fellowship at the MIT Media Lab in 2014, Neistat created a tech company that has since created a number of video apps, including Beme and Top Five Live. (Beme has so far been downloaded as least 1 million times.) For the 2016 election, he launched Exit Poll, which allows users to tell the world that they voted and why.

So what will Casey 3.0 look like? He hopes he'll be able to expand beyond YouTube fame and, perhaps, go a little more "mainstream." (As if getting stopped on the streets of Cuba or anywhere else in the world wasn't mainstream enough.) Neistat still plans to post regularly to YouTube, but he's also eyeing other platforms.

"Your career is the jungle, and you're Tarzan trying to get to the other side," he says. "You're swinging from vine to vine, and the vine I'm holding onto right now is vlogging, and it's the biggest, best vine ever. But I'll never be able to grab onto the next one until I fully let go of this vine."

Check out the rest of this year's Hot List honorees:

This story first appeared in the November 28, 2016 issue of Adweek magazine.

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