Continuity mistake: Dr. Myshkin arrives at Frasier's from the Russian embassy to discuss the bear clock. He puts a diary on the coffee table where it sits to the right of the vodka, near Niles. Suddenly in one shot it has moved to the left, near Frasier. Later in the scene it has switched sides again.
Continuity mistake: When Marty, Niles, and Frazier return from the taping of the Antiques Road Show, Marty hangs up his blue windbreaker and then Frazier hangs up his gray raincoat, obscuring Marty's coat. But throughout the scene, all we see is Marty's blue jacket - where did the raincoat go?