In every movie you can see/notice things that strange, odd, funny or weird that may or may not have been intended on being seen/heard. This includes mistakes, weird reflections, pictures, lines, accents, faces and people.

For a few examples:
During the Triwizard Tornument, in the First Task, when Harry has gone missing and has disappeared from view (after being chased around the skys over the stadium and school by the dragon), sitting in the grown up's area of the stands is a woman who I could swear was JK Rowling. I may be imagining things but I could swear it was her.

Hermione, after the second task, kisses Harry's head.

After the second task, Hermione puts on a funky French accent when she tells Harry that he isn't last to finish because Fleur never got to or rescued her hostage. When Hermione says Fleur never got past the grindylows, it sounds a bit more like "ze grindylowz."

The pictures didn't move in the scene where Harry sees Karkaroff's tattoo of the Dark Mark; he has a conversation with Snape in the hallway and the pictures on either side of Snape don't move.

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Did you see/notice something odd? Tell me about it!