Answering Machine
In Season 7 Episode 3: Diamond Jack, we have the case of a rather peculiar answering machine. You see it was in this episode that the roommates get an answering machine but you never see it again in the series!
Oops
Whoopys, during the examination scene in the Doctor’s office of season 6, episode 20, Jack mistakenly calls Janet as Mrs. Fordwick instead of Mrs. Foster. This mistake even draws some minor laugh from the audience.