The One Where Rachel is Late - S8-E22
Other mistake: Ross wants Rachel to change, but she claims that it is 100° out. Monica and Chandler got married on May 15, the day Rachel was officially pregnant. 9 Months after May would be Febuary. It would be cold out.
The One Where Rachel is Late - S8-E22
Continuity mistake: In one scene, Rachel is using the bathroom. She yells out to Monica and Phoebe "Whose turn is it to help me get up?" A few scenes later Rachel goes to the bathroom again, but gets up with no one helping her. (00:07:05)
The One Where Rachel is Late - S8-E22
Plot hole: The times in this episode vary a lot. Monica and Phoebe first bet about Rachel giving birth, then it goes to the scene with Joey and Chandler at the movies. It then returns to Monica and Phoebe the next day with Monica losing the bet. However, a little while later, it goes back a day and shows Joey and Chandler at the movie premiere again. (00:09:00)
The One Where Rachel is Late - S8-E22
Continuity mistake: The first time Phoebe and Monica are making bets on when Rachel will give birth, Phoebe has a bottle of water in her hand and is holding it near her stomach. She puts it to her mouth to drink some, but in the next shot, the bottle is near her stomach again. (00:07:00)
The One Where Rachel is Late - S8-E22
Visible crew/equipment: After Rachel has told Ross it's 100° outside and she starts walking towards the door, a camera is visible to the far right (Widescreen version only). (00:09:30)
The One Where Rachel is Late - S8-E22
Continuity mistake: At the end, when Rachel and Ross leave for the hospital, Rachel grabs the keys. In the close-up, when Rachel asks, "Do you think we have time?" she holds the keys up in her left hand while Ross holds her empty right hand. It then cuts to a medium shot, and the keys are now in Rachel's right hand, the same hand Ross holds. (00:20:40)
The One Where Rachel is Late - S8-E22
Other mistake: Rachel's water breaks, but her skirt is completely dry.
Answer: Usually by the seventh night of Hanukkah you don't know what to get the other person, and you will probably resort to getting the other person something insignificant. Chandler is basically saying that the pen is a stupid gift.