Fight Club
Another pausable moment in Fight Club is actually an ongoing theme throughout the whole film. David Fincher sneaks a Starbucks coffee cup in almost every scene. Whether there was some kind of brand deal or Fincher just did this for his own enjoyment, it's so easily noticeable once you know to look.
Toy Story 3
If you look closely at the garbage man’s shirt in Toy Story 3, you’ll recognize it as matching the one that the terrifying bully character, Sid, wears in the first film. Maybe they're the same character? We'll let Reddit debate that.