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.
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.
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?"
5) "Glee" Dreams On
Mr. Schue and NPH team up for a "Glee" -tastic rendition of Aerosmith's "Dream On."
Watch More Videos of the Week:
Last Week's Videos 
- Viral Videos