The scene where Joey says he wrote complicated medical terms on props to remember them better when shooting his part as Dr. Drake Ramoray on Days of Our Lives (1965) is a reference to George Clooney who is famous for doing the same thing when he played Dr. Ross on ER (1994).
Magna Doodle: A scene from Aesop's Fable, "The Fox and the Grapes." (The fox, snapping at the grapes, just out of reach)