1.In Pretty Woman, the opera Edward takes Vivian to is called "La Traviata." The opera is about a prostitute who falls in love with a wealthy man, which mirrors Edward and Vivian's storyline in the film.
2.In Notting Hill, the wedding cake at the end of the film has a goat playing a violin on it. This is a reference to a painting both Anna and Will own.
3.In Sleepless in Seattle, Sam tells his son Jonah that one of the things he loved about his late-wife was how she cut the peel off an apple in one long curly strip. A few scenes before, you see Annie peeling her apple in the same way.
4.In Never Been Kissed, Josie wears a pilot pin. When Josie becomes popular, the popular girls start wearing pilot pins, too.
6.In Four Weddings and a Funeral, on Charles' wedding day, he's told that getting married is "...Pretty easy. Just say 'l do' whenever anyone asks you a question." The only question Charles is asked when he's at the alter is if he loves someone else, and his reply is "I do."
7.In You've Got Mail, Kathleen buys flowers from a pregnant-looking florist at the beginning of the film. Later in the film, we can see an "it's a girl" sign in the flower shop.
8.In 10 Things I Hate About You, when the doorbell rings before the hoards of teens crash his party, Nigel says, "That must be Nigel with the brie." The first teen who comes barreling through the door is, in fact, Nigel with the brie.
9.In Jerry Maguire, Renee Zellweger's iconic line is, "You had me at hello." In Shark Tale, Angie (voiced by Renee) smiles when Oscar repeats this exact line.