On April 23, to celebrate the release of his fourth solo album, Willpower, will.i.am joined collaborators Britney Spears, Miley Cyrus and Nicole Scherzinger in a live Google+ Hangout on his illwilly YouTube channel.

Spears, who joins Will on tracks such as "Scream & Shout," "Big Fat Bass" and "Femme...

Cheech and Chong have been smoking weed consistently since the 1970s, man. They're even starred in some of the most successful stoner comedies of all time, Up in Smoke, Cheech and Chong's Nice Dreams, and on and on. So who better to gather on 4/20 and test some of the most famous stereotypes about pot? Some of our very officially and peer reviewed experiments include:

- The Memory Test: Can Cheech and Chong remember facts about their own movies?
- The Munchies Test: Will the guys go for Cheetos or veggies?
- The Hackysack Test: Do the guys want to get in on a hack?

And much, much more. Want to see how they scored? Afraid they may have set the cause of stoner equality back 40 years? Check out the video and find out!

Catch Cheech & Chong's Animated Movie now in theaters.

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Doug Benson's documentary Super High Me followed the comic as he gave up weed smoking entirely for a month (the horror!) and then smoked constantly for another month. Ever since, he's been scanning about for his next great movie idea. Now, Benson's releasing "The Greatest Movie Ever...

Grammy Award-winning rapper Eve is making her big comeback on the music scene with Lip Lock, her first new album since 2002's Eve-Olution. She stopped by What's Trending to chat with Shira Lazar and Ross Everett about working on the new tracks, major collaborations, and what on Earth she's...

Beauty and fashion gurus Elle and Blair Fowler stop by the What's Trending to chat about the hottest seasonal trends, how to pick the perfect phone case for your outfit, and what's in store for 2013.

Along with their successful YouTube channels, makeup line, Beneath The Glitter novel, and accessory line with JustFab.com, the sisters also launched their own line of stylish phone cases at cellairis.com.

"We developed this line thinking you change your bag and your shoes out for your outfit, but your phone is always in your hand, so why wouldn't you go head and change that out, too?" Blair asks.

"We launch them to go with the fashion season," Elle adds.

Adding to that, Elle and Blair have designed shoes and handbags, so possibly a full fashion line could be coming up in the future.

As girl talk gets rolling in the studio while critiquing a "Swaggy" Justin Bieber case, the girls chime in to reveal their feelings towards the Biebs.

"Justin Bieber does have swag. No matter what you want to way, think about the way he dances," Blair says. "We've seen him perform live at the Teen Choice Awards and he really... he has a presence. He has swag."

So, if Justin has his Swag Army, shouldn't the Fowler sisters have their own army of fans? What do you think their legion of viewers should be called?

Finally, we ask Elle and Blair to give their opinions on some crazy Fashion Week runway looks and trends, featuring designs from Betsey Johnson, Jeremy Scott, Eckhaus Latta and The Blonds.

Check out their website for more fashion tips and look out for their second book coming out the fall!

In Channel Surfing #9, Creators Project takes a behind the scenes look at the making of Daft Punk's upcoming album Random Access Memories with Giorgio Moroder, Vice's The Cute Show stops by Pet Kingdom in Fort Meyers Florida to visit some of the adorable and exotic inhabitants, Cartoon Hangover provides...

Reddit asked for a Rob Zombie AMA (Ask Me Anything), and while he has yet to jump on the bandwagon, we've got those redditors covered in this segment where we ask the man himself those hard-hitting questions about his past work and Lords of Salem movie, premiering April 19.

We're geeking out in the What's Trending studio with a huge science-fueled chat, featuring NASA's Flight Director and iconic Mohawk Guy Bobak Ferdowsi, Veritasium's Derek Muller and I Fucking Love Science's Elise Andrew.

First, we positively have to know how it's looking out there on Mars. "The water looks like fresh water that you might find on Earth," Ferdowsi says, noting that the water contains ingredients that could sustain life.

Alas, the Rover mission team is actually on vacation because Mars is currently moving to the other side of the sun, and while the station does get daily updates from the Rover, they're not transferring a great deal of information at this time.

While Elise Andrew is used to getting the "women in science" question (many people did not realize the FLP community was run by a woman), she says she doesn't understand why people were so surprised about her involvement in the field.

"I think people are just not up to date necessarily on what science and engineering looks like nowadays," Ferdowsi chimes in to say.

A huge part of broadening science education is taking place right here on YouTube, with Mueller as a prime example of those leading the charge with educational channels and content. "I actually spent my PHD -- three and a half years of my life -- studying how to make a good educational video about things in science," he says. "What you need is more context," he adds, noting the importance of destroying people's preconceived notions and starting an engaging discussion.

Mueller excitedly identifies the Higgs Boson as discovery of the century and something that makes him anxious about  developments in the field of genetics. He says, "Figuring out, for example, the role of junk DNA and being able to sequence DNA much faster than before and much cheaper than before."

For those looking to break into the science education community online, Andrew and Mueller advise embracing social content and taking risks with your material. Andrew stresses consistency. She urges people not give up if people don't respond right away as it takes time to build up a following.

Regarding her own work, she's been asked to write a book and do a TV show but, she admits, "I just want to keep doing what I'm doing at the moment, which is showing people everything that I think is amazing." Eventually, she'll choose the appropriate format through which to expand her community.

When choosing what to share, she relies more on instinct about the "cool" factor. "If you're talking about what engages people more, it's always medicine and it's always astrophysics," she says. "But science doesn't tend to have trends in the same way the news does."

In terms of major discoveries yet to unfold, Ferdowsi says, "I think this is the year where we're going to see some big announcements on Earth-like planets outside of other stars." He continues, "Today's Mars is not necessarily the best place for life, but there are moons of Jupiter like Europa for example or the moon of Saturn, Titan, that look really promising."

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Jesse Wellens, the male half of YouTube's hottest prank channel, PrankvsPrank, joined What's Trending live via Google plus to talk about maintaining how they were one of the first to build out a prank based channel on YouTube and how that's impacted their relationship as a real life couple.

YouTube stars Shay Carl, Ed Bassmaster, and Charles Trippy also crash the interview while filming Shay's "I'm Vlogging Here" documentary!

As someone who makes a living executing masterful pranks, Wellens says that April Fools' Day was actually an impossible time to pull anything off. "We were both so on edge," he says of himself and girlfriend, Jeana. "it was impossible to get to each other."

Though it might seem difficult to keep the relationship steady when they're constantly looking for way to one-up each other, Jesse says, "Our therapy is the pranks. After it's all said and done, we watch it and we love it." Jeana even pranked him on their first date! It was meant to be.

One of the most viral pranks is the proposal prank, because, as Jesse points out, the couple actually ends up pranking the audience because fans are always wondering when Jesse and Jeana will get married. "It was like prank-ception."

When it comes to devising the ultimate prank, nothing is off limits. In terms of rules, he says, "We always break them because those are usually the best pranks."

And now Jesse is even branching out into the music scene. "I'm working on something pretty big that my viewers are definitely going to be excited for. They know I've been in the studio," Jesse teases. "It's going to be a rap song, but it's something that they know I've been meaning to do for a long time." Stay tuned to his Prank vs Prank and bfvsgf channels for more!

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Californian music duo Brandon & Leah treat the What's Trending studio to a live performance of their song, "Showstopper," widely known as the theme song from Kourtney & Kim Take Miami. The couple also chat about married life, their upcoming "Cronies" EP and teaching their dog to surf.

Having...

In Channel Surfing #8, What's Trending presents the best of YouTube's original channels this week!

Felicia Day celebrates Geek and Sundry's anniversary with new shows, Machinima Prime launches the first episode of Player vs. Pain, Jesus gets into the Draw My Life meme, Victoria Floethe educates us about bras, World of Heroes pays tribute to "The Walking Dead" and Petody: Snail is quite possibly the best thing ever!

FEATURED VIDEOS
Felicia's at the Beach and Has an Announcement
Player Vs. Pain: Episode 1
Draw My Life: Jesus
Victoria Floethe Dances in Her Bra
Cosplay Piano
Petody: SNAIL

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G.I. Joe: Retaliation director Jon M. Chu stops by What's Trending to chat about converting the upcoming film to 3D, working with Channing Tatum and The Rock, and how this film will blow the first out of the water!

YouTube film experts Peter Rallis of Movie Buzz and Grace Randolph of 

Machete himself, legendary actor Danny Trejo, stops by the What's Trending studio to chat about raising money for his Snap Shot film on, the three Bs of fantastic filmmaking, and the future of his Machete films.

Marking Trejo's second project with director Frankie Latina (Trejo previously appeared in Modus...

Singer/songwriter Tony Lucca recently exploded into nationwide stardom after becoming a finalist on the third season of NBC's The Voice talent competition series. With season 4 premiering last night, Lucca stopped by What's Trending to tease the new batch of contestants, chat about working with judge Adam Levine on his own upcoming...

Lucas Cruikshank a.k.a. Fred Figglehorn stops by the What's Trending studio to talk about his new Nickelodeon show, Marvin Marvin, the future of "Fred," and his knowledge of pop culture's most famous aliens.

Following up from The Fred Show, based on his hyper YouTube character, Lucas is now...

Neil Hopkins and Brea Grant stop by the What's Trending studio to talk with guest host Kevin Pereira of the now sadly defunct Attack of The Show about the high risk and high rewards of indie filmmaking with their new thriller movie, Detour, which hits theaters and VOD on...

Comedian TJ Miller stops by the What's Trending studio to talk about HBO's Silicon Valley, The Warner Sound's "Gorburger" show and react to some of pop culture's finest actors turned singers.

"Mike Judge is very specific about how people look in his projects and I think it's because...

NBA sensation Jeremy Lin chats with Shira Lazar at SXSW about his brand new documentary, "Linsanity" the movie, appearing in various YouTube videos and the overall message he wants fans to take away from his new film.

"I think it was unique. I think it was something that had never happened and not just from a basketball standpoint," Lin says of his underdog tale. "All the different elements of the story, whether its being Asian-American, the basketball, the faith or Harvard. There are a lot of different areas or target audiences that can possibly appeal or relate to the story."

He's also no stranger to the YouTube scene, having collaborated on funny shorts with huge YouTubers like Ryan Higa and KevJumba. For the record, "How To Get Into Harvard" is his favorite.

Regarding his presence in the online press, Lin says that he tries to steer away from reading all the chatter: "I don't have Google alerts on myself, but my parents do."

Finally, he points out what he'd like viewers to take away from his new film: "The main themes of the film is, first, my faith, how big of a role it was for me and is for me," adding, "other things like pursuing your dream and, whether its unconventional or not, perseverance."

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Public Enemy hip hop sensation Chuck D stops by the John Lennon Educational Tour Bus at SXSW 2013 to talk about being inducted into the Rock and Roll Hall of Fame, his Evil vs Heroes instrumental album, and the new digital label for independent artists, SpitDigital.

"I think it's...

M1 and Stic Man from Dead Prez stop by the John Lennon Educational Tour Bus at SXSW 2013 to talk about the new album, Information Age, the RBG Fit Club, Million Miles Movement, and where the future of music is going with streaming services like Rdio and Spotify.

Among Dead Prez's body of work, Stic says that "Information Age" is much more introspective. "Ultimately, it's about that inner awareness developing, cultivating that so we can have the lives we want to have, so we can be more effective as change makers and human beings."

Even though it's been a while since the duo released a full album, M1 assures us that they've been hard at work, putting out mixtapes, working on their "Turn Off the Radio" series and Stic dropping his workout album.

Stic also promotes the RBGFitClub.com and Million Miles health and fitness movement, with the Million Miles March coming up, which will inspire one million miles collectively through cycling, walking, and running.

On the evolution of hip hop, M1 says, "It's totally international. Stuff sounds as electronic as it ever did. It used to be so root and grounded and muddy and dirty."

Stic adds, "It's a universal language of the youth on the planet."

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