Stephen Colbert's days as host of The Colbert Report are winding down, which of course means big surprises and impromptu cameos. Last night's might have been the biggest when President Obama rolled in and straight up took over for "The Word."

"How hard can this be?" quipped Obama. And like that The Obama Report was born. 

Check out more Stephen Colbert before he's gone forever (or at least until 2015)...

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