Now without me explaining it in detail again, go to wikipedia to bone up on the golden mean...
This still from Ratatouille shows off composition by the golden mean quite nicely:
- The Horizon is set at the major vertical subdivision
- The river occupies the lower left corner, and again at a major horizontal subdivision
- Further subdividing the right part of this frame, again the character and his rooftop perch are composed according to various golden ratio subdivisions of the frame
- The space occupied by the character is itself a further subdivision according to the golden mean
- As is the ratio between the base width of the character to the neck
- You can see the Eiffel Tower and the dome in the distance, two major features which break up the horizon, also lie on significant golden ratio points.