I was very excited to see the American Reunion movie. I saw American Pie just after college and remembered it was quite funny.
Jim, Michelle, Oz, Heather, Stifler reunite for their high school...
Well, it was really his grandmother, but his young mind turned it into a ghost because it couldn't handle the fact that it was a member of his family molesting him.
Many people can learn from Abbott & Prospero. Subsequent jokes in this thread are doomed. Is the poster near a light? If so, the light may warm the poster frame/casing, causing it to expand. Cooler night temperatures would cause the warm frame to contract, which might result in tapping noises.