Continuity mistake: During the opening scene in the cafe, Roz is picking up and putting down her coffee & muffin, but all shots from behind show her holding the coffee.
Continuity mistake: Niles is in the police station talking to Frasier and as he says "What happened?" one hand is holding a coffee cup and the other is on his hip. As the shot changes, both of his hands are on the coffee cup. (00:13:20)
Continuity mistake: In the scene where Frasier, Martin, and Niles are in the kitchen putting candles on Freddie's birthday cake, you first see the Louis Pasteur cake facing Frasier. The camera pans out and then back in. When it does, the cake has turned around. The camera pans back once more, and the cake is back to its original position.
Chosen answer: The turkey's stuffing.