It’s the Trending Now Top 5 Countdown for Halloween 2012, 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 the most amazing “Aliens” father/daughter Halloween costume ever to an Epic Rap Battle between Doc Brown and Doctor Who, we have you covered right here on What’s Trending.

#5: Aliens Power Loader Baby Costume

#4: A Message from the Greatest Generation (NSFW)

#3: GANGNAM PILE – Summer Pop Medley 2012! / Ghetto Gangnam Style

#2: Epic Rap Battles of History Season 2: Doc Brown vs. Doctor Who

#1: The Future of Star Wars Movies

One More Thing!: Dogxter – Morning Routine

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[Image via b3ta.com]