Barack as "The Master".

[Nukie 2]

                         "Ohhh Manos, Lord of Primeval Darkness!"

image from www.icanihascheezburger.com (though they got it from somewhere else, but neverless they'll probably attach a code to this so it will disappear after I post this, thus making myself look like a total jackass to every badmovies.orger; who will say "I can't see it")

[Rev. Powell]

"Yesterday you were just a student, but today you graduate and go out into the world as a certified teleprompter.  Thousands of politicians who can't think for themselves will depend on you, so please, take this responsibility seriously."

[indianasmith]

"And now, young Jedi, you will die . . . "

[AndyC]

"Hey, aren't you Callista Flockhart?"