While playing poker, Mrs. Moon says "I've got Aces over Deuces." This would be a full house made up of three Aces and two 2's, but in her hand you can clearly see a Queen being 1 of the 5 cards.
Daphne: (finally telling her mother she's not a virgin) You remember that boy you hated so much? He was my first...right in the parlor where you take your tea!
(Frasier's been kept awake several nights because of Cam's draping a giant American flag over his window)
Daphne : Still awake?
Frasier: Yes. It's almost the dawn's early light...and our flag is still there...
(After Frasier ruins Simon's night with a woman)
Simon: (To Frasier) Well you're just a giant contraceptive, aren't you?
Title: Mother Load
The episode title shares a similar name to the 1982 film "Mother Lode".