The Great Voice Robbery - S1-E3
Audio problem: Several times throughout the episode while the characters are speaking in other people's voices the spoken words don't match the lip movements.
Firefly, Light My Fire - S1-E1
Revealing mistake: Courage winces and reacts before the stereo-zapper is fired.
Firefly, Light My Fire - S1-E1
IQ: How do you expect to carry out your duties as a firefly? You'd look pretty silly walking around at night.
Sparky: Oh, I never go out at night, I'm afraid of the dark!
Lady, You Don't Look Eighty - S1-E13
Trivia: Caroline Ellis (Joy) references her actual birthday of October 12 when she complains the boys forgot it.