Something that has always struck me when watching Close Encounters of the Third Kind, was this apparent reference in John Williams' main theme (starting at 4:28) to Leigh Harline and Ned Washington's When You Wish upon a Star as used in Walt Disney's Pinocchio.
Does anyone know if this is indeed a homage, and, if so, why this particular motif was used?
My current guess is that it's (early) Spielberg's love for infusing his films with a certain amount of 'fairy-taleness', and naivete (in the purely positive sense), and the obvious reference to space as a benevolent force, but I'm sure Williams could have achieved those things with his own creative force alone.
Some additional trivia:
Richard Dreyfuss's character Roy Neary has a relatively lengthy conversation with his oldest son, Brad, about going to see Pinocchio. Apparently Spielberg, with this seemingly trivial and chaotic scene, is already preparing the audience's subconsciousness in preparation for the theme. (Transcript can be found here).