It’s the Trending Now Top 5 Countdown for March 21, 2013 – where we gather the hottest and most outrageous must-see YouTube videos hitting the web today and send them all straight to your screen. It’s like watching the best of YouTube — only faster!

From Obama’s NCAA bracket to the new “Star Trek Into Darkeness” trailer, we have you covered right here on What’s Trending.

#5: Sifl and Olly Video Game Reviews – Episode 1

#4: TIE: Barack-etology / Kid President NCAA Tournament Bracket 2013

#3: Star Trek Into Darkness – International Trailer

#2: Imaginary Friend Photo Prank

#1: Tina Fey Revives Sarah Palin Impression on Inside the Actors Studio

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