In this week's 10 viral videos that had everyone buzzing: Justin Bieber bumps his head, Lady Gaga takes a bite out of Barbie, Muse debuts its "Neutron Star Collision" from the latest "Twilight" movie, Janelle Monaé busts a move, and more.  

1) So, Justin Bieber Walks Into a Door...

...and, bam! Ouch. Don't worry, ladies, he's taking it in stride. "Yo, what up!" he tells the cameraman that caught his head bump. "I just walked into that door. I don't know if you seen it." Actually, Justin, about 906,000 of us have seen it, and counting. 

Bonus Tween Trauma: Lady Gaga lives up to her "Monster" persona by biting the head of a Barbie doll onstage. Hasn't she ever seen the Gaga Barbies? (Watch) 

2) Muse Debuts "Neutron Star Collision (Love Is Forever)"

Watch R. Pattz and T. Laut try to out-smolder each other in the video for Muse's new "Twilight Saga: Eclipse" single.

Bonus Premiere: Fergie lends David Guetta a hand for "Gettin' Over You," the latest single off the French DJ's album that is destined for "Jersey Shore"-style, fist-pumping greatness. (Watch) 

3) Janelle Monaé Busts a Move on 'Letterman' 

The funky soul singer makes her national TV debut with "Tightrope" on "Late Show with David Letterman." James Brown would be proud.  

Bonus Shaking of Tailfeathers: Seven-year-old girls create an "uproar" by dancing to Beyoncé's "Single Ladies." Inappropriate, impressive or both? (Watch) 

4) Owl City Spoofed on "Electronic Wuss"

Come ride with the Key of Awesome in their "sensitive balloon" as they make fun of "Fireflies" hitmaker Owl City and his surrealist lyrics. "I couldn't make my punches land/I noticed I had lobster hands/Then a snake wearing a vest, said did you study for the test?" 

Bonus Bad Imitation: Ryan Phillippe does his best Snoop Dogg impersonation on "Lopez Tonight." Not best meaning good, but best meaning bad. (Watch) 

5) "Glee" Dreams On

Mr. Schue and NPH team up for a "Glee"-tastic rendition of Aerosmith's "Dream On."

Bonus Cover: "American Idol" cast-off Casey James visits Ellen DeGeneres to perform Ray Charles' "I Don't Need No Doctor." (Watch) 

Watch More Videos of the Week:

Rick Ross Gets 'Super High'

Josh Barry Wows on 'Britain's Got Talent'

Last Week's Videos