* The Pixar Ball (Luxo Ball): This iconic red-and-yellow ball, which first appeared in the short film "Luxo Jr.", often makes a cameo in Pixar films, sometimes subtly hidden.
* Pizza: Pizza seems to be a staple in many Pixar films, perhaps reflecting its popularity in American culture.
* A "Hidden Mickey": These three circles, sometimes subtly incorporated into a background or design, are often found in Disney films, including Pixar's.
* The Pixar lamp: This jumping lamp, again from "Luxo Jr.", is a recurring symbol and is often used in the intro sequences of Pixar films.
* Easter Eggs: Pixar is known for its hidden details and references, which can be anything from other films to pop culture to inside jokes.
Ultimately, while no single element appears in *every* Pixar film, the presence of these common elements contributes to the feeling of a shared universe and a sense of playful detail that fans enjoy discovering.