The One With The Cooking Class - S8-E21
Continuity mistake: The night before they go to the baby furniture store, Ross and Rachel are in the kitchen talking. Just before they leave the kitchen watch Rachel's robe: in one shot the 'lapels' are neatly one over the other, and in the next shot one lapel has moved lower and looks halfway folded over as if she hastily pulled the robe together. (00:03:15)
The One With Rachel's Date - S8-E5
Continuity mistake: When Rachel asks what Kash said, her arms are outstretched, the ext shot they are together and when the camera cuts again and they have moved yet another time. (00:06:55)
The One Where Rachel Tells... - S8-E3
Continuity mistake: When the airline representative states the first class seats are gone, her head leans away from the camera. The shot changes and it's leaning to the camera. The camera is in the same place. (00:07:10)
The One Where Rachel Tells... - S8-E3
Continuity mistake: When Rachel and Ross are at his apartment, Rachel is holding some magazines. The way she holds them changes depending on the shot. (00:09:35)
The One With The Red Sweater - S8-E2
Continuity mistake: When Chandler mentions about the disposable cameras to Monica to cheer her up, Joeys hands are together. Next shot they are apart. (00:00:50)
The One Where Chandler Takes a Bath - S8-E13
Continuity mistake: When Chandler is in the bath with Monica at the end a splodge of bubbles appears on his face between shots. (00:20:40)
The One Where Rachel Tells... - S8-E3
Continuity mistake: When Rachel says Ross can be involved as much as he likes, his arm moves from by his chin to in his lap when the camera cuts. (00:11:25)
The One Where Rachel Tells... - S8-E3
Continuity mistake: In the deleted scene on the DVDs Chandler is leaving the security interview with his holdall over his shoulder by the short strap. The camera cuts to outside the room and the holdall is now level with his legs. (Mistakes in Deleted scenes are valid if they are only in that scene which this is.) (00:24:50)
The One Where Rachel Tells... - S8-E3
Continuity mistake: In the deleted scene on the DVD, Chandler puts his plane tickets in his shirt pocket. Next shot the tickets have reversed. Look at the blue section. (Mistakes in deleted scenes are allowed if they are in that scene.) (00:25:00)
The One Where Chandler Takes a Bath - S8-E13
Continuity mistake: When Chandler takes hold of the boat he grabs the middle of it, the camera changes angle and he is now holding it at the end of the boat. (00:06:20)
The One Where Joey Tells Rachel - S8-E16
Continuity mistake: When Monica is talking to Ross about how Joey feels, there is a shot of Monica bending down to talk to Ross, and some magazines on a table. At the end of the scene the magazines have changed place. (00:05:30)
The One With The Birthing Video - S8-E15
Continuity mistake: In the one where Chandler watches the video of a woman giving birth, he takes a video out of the VCR and places it on the table (he's staring at the box and when Monica moves it we hear that a tape's inside). When Monica enters the room, she asks him what he is so upset about and he presses play on the remote control. The tape immediately starts playing, despite no-one moving to put it in the player. (00:06:30)
The One Where Rachel Has a Baby, part 2 - S8-E24
Visible crew/equipment: After Rachel asks Joey to get the other box of tissues under Ross' coat, when Joey drops the ring box then picks it up and opens it we can see the end of the hospital set floor and wall, behind the chair.
The One With The Secret Closet - S8-E14
Other mistake: When Chandler stops by to see how Joey's doing after Rachel has moved out, Joey's holding a gallon jug of Minute Maid orange juice with its brand name partially painted to hide it, so it now reads "Vinut Vaio" on the label.
The One Where Rachel Has a Baby, part 2 - S8-E24
Continuity mistake: When Ross is telling Chandler that Janice is there and she's contracting Chandler can be seen putting his hands on his face. In the very next shot his hands are by his side again. (00:02:50)
The One With The Secret Closet - S8-E14
Continuity mistake: When Chandler mentions how long Alexandra has been massaging Monica, he is holding a bowl,and he walks away with it. But when Monica says to Phoebe, "you can understand why this would be weird for me", the bowl is on the table. (00:05:20 - 00:06:00)
The One In Massapequa - S8-E18
Audio problem: When Monica is preparing her speech, she stands up to show Chandler her note card, but when you can hear her say "Hey, check this out," her lips don't move. (00:02:20)
The One Where Rachel Tells... - S8-E3
Continuity mistake: Joey hits the blue robots head down. The camera changes and the head is back up. (00:07:25)
The One With The Red Sweater - S8-E2
Continuity mistake: When Ross is explaining about buying more cameras, the way he holds it changes. Follow the lens. (00:08:40)
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.