Similar to the Hot Carl, in the sense that you take a dump on someones face but it is done out of vengeance rather than for pleasure. The Hot Carl Sagan is particularly reserved for people who are smug, self-righteous or know-it-alls.
My boss is such an asshole. She thinks she knows everything and treats us all like we're children. One of these days, I'm going to have to take a trip to Taco Bell, tie her down to her desk and deliver a steaming Hot Carl Sagan to her stupid, self-righteous face.