If you're going to kill eight minutes of time on your show, there are worse ways to do it than a lip-sync off between Jimmy Fallon and John Krasinski. We'll probably watch Krasinski throwing down to "Teenage Dream" a few times today.

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  • Stephen Colbert

    <a href="http://www.snakkle.com/galleries/before-they-were-famous-stars-tv-late-night-hosts-then-and-now/" target="_hplink">To see even more late night hosts before the fame, <strong>click over to Snakkle!</a></strong>