1.In Elf, Buddy mistakenly gets his dad lingerie for Christmas. At the end of the film, it's clear that Walter regifted the lingerie to his wife, Emily.
2.Also in Elf, Peter Billingsley from A Christmas Story makes a cameo as one of the elves.
3.In Four Christmases, Peter Billingsley also makes a cameo.
5.Also in How The Grinch Stole Christmas, the bills say "One Whodollar" and the coins say "E Pluribus Whonum," which is a play on American currency.
6.In The Muppets Christmas Carol, the store seen behind Scrooge is called "Mickelwhite's." The birth name of Michael Caine — who plays Scrooge — is Maurice Joseph Micklewhite.
8.In Home Alone, Harry's tie clip is in the shape of a firearm.
9.In Gremlins, you can see a machine flash into and then out of the frame behind the dad in the phone booth. The machine is actually from the movie The Time Machine.
10.In Love, Actually, Sam calls his step-father 'Daniel', but by the end, he calls him 'Dad'. This is one of the only successful love stories in the film.
11.In The Polar Express, every direction on the compass is "south" because everything is south of the North Pole.
12.In National Lampoon's Christmas Vacation, you can see the outline of Eddie's mockneck under his sweater.
13.In The Santa Clause, when Scott is in denial about being Santa, his Converse are black. It's only when he accepts his role as Santa does he finally breaks out his red Converse.
14.In Christmas With The Kranks, Luther and Nora are wearing the same bathing suits that we saw in the advertisement at the beginning of the film.
15.In Just Friends, the Snowman's face is now frowning after everything got destroyed.
16.In A Charlie Brown Christmas, during Linus's speech, when he says, "Fear not," he drops his security blanket.
17.In Die Hard, we see Ellis doing cocaine earlier in the film. It is clear that someone misinterpreted him when he is later brought can of Coke in the film.
