The One With Joey's Big Break - S5-E22
Continuity mistake: When Joey arrives in the desert there is a lot of stuff not in vans. As the director gets into his car, loads of equipment is still in the desert, but a few shots later the vans are full and leaving. (00:18:50)
The One In Vegas, Part 1 - S5-E23
Continuity mistake: Chandler comes down to find Monica and sees that she's playing some game and having fun. He makes a sad and dejected face. The scene cuts back to Monica, and then to the exact same shot again of Chandler making the sad and dejected face. (00:22:00)
The One In Vegas, Part 1 - S5-E23
Continuity mistake: After Joey tells Chandler about his identical hand twin and plans for getting rich, when he sees Chandler's reaction Joey asks, "Are you unsupporting me again?" while he lifts his left arm and points accusingly at Chandler, but next shot it's Joey's right arm that's up and pointing.
The One In Vegas, Part 2 - S5-E24
Continuity mistake: When Rachel is saying to Ross that the pen won't come off, a wheel behind Rachel is spinning or stopped dead in different shots. This includes instant cuts between the 2 angles. (00:12:35)
The One In Vegas, Part 2 - S5-E24
Continuity mistake: When Monica puts the blue jumper up her dress, she lifts it up and you can see she is wearing black jeans underneath. The next scene shows her running off without the jeans underneath her dress. (00:18:55)
The One In Vegas, Part 2 - S5-E24
Continuity mistake: When Pheobe is telling the Lurker to go away her hand is in the cup of coins, an instant cut later and it's out with no time to do so. (00:29:00)
The One In Vegas, Part 2 - S5-E24
Continuity mistake: When Monica and Chandler find the dice under the craps table, it is at an angle so both the four and five appear up. When the camera changes to the last shot (the zoom in of them kissing) the dice is sitting flat on the floor. (00:33:35)
The One In Vegas, Part 2 - S5-E24
Continuity mistake: When Monica and Chandler kiss under the table, as "Everybody Loves Somebody" plays, Monica is shown smiling. She then closes her mouth. In the next shot, she is smiling again without any time to do so.
Continuity mistake: The white dog that Joey gives Chandler sometimes has red lips and sometimes does not.
Continuity mistake: In the previous episode, Ross rings the helpline of the makers of the pen and is told the pen won't come off. Yet in this episode it vanishes from Ross and Rachel's faces between getting up and going to breakfast. (00:02:25)
Continuity mistake: When Ross and Rachel are in bed, and Rachel says she remembers laughing a lot, and Ross says "Then we didn't have sex," Rachel turns her head away from Ross twice. (00:03:10)
Continuity mistake: During breakfast, when Joey and Phoebe are talking about driving back, the fork in Phoebe's left hand disappears and reappears. (00:03:55)
Continuity mistake: Joey's Hand moves from putting it to his mouth to the plate instantly at breakfast. (00:06:35)
Continuity mistake: When Joey and Chandler talk about how to tell Monica that it is too soon for marriage, Joey fills his plate up with scrambled eggs. When he walks over and sits at the table, the eggs appear smaller on his plate. (00:15:54)
The One Where Ross Hugs Rachel - S6-E2
Continuity mistake: In the scene where Rachel is all happy that the three of them are going to live together, her arms keep changing position throughout the scene. (00:08:35)
The One With Ross's Denial - S6-E3
Continuity mistake: When Monica and Chandler are eating, Monica's plate holds a sandwich and chips. When Joey comes in, Monica's plate contains no chips, and when he leaves the chips are back again. (00:04:00)
The One With Ross's Denial - S6-E3
Continuity mistake: When Joey is interviewing the potential roommate and Chandler comes in, Joey's stance changes a few times. His grip on the application form changes, and when he points to the bathroom his arm is in a slightly, but noticeably, different place in the next shot. (00:11:10)
The One With Joey's Porsche - S6-E5
Continuity mistake: When Ross is talking to his divorce lawyer there are 2 pens in a holder on the desk. Throughout the scene they vanish and appear randomly. (00:10:50)
The One With Joey's Porsche - S6-E5
Continuity mistake: Phoebe knocks over a vase and has to clean it up because "Let's face it; we're at Monica's." When she turns back around and notices one of the babies is missing, the baby on the right (in the striped top) falls over towards the other baby. A split second later when the shot changes the baby is sitting upright again. (00:15:15)
The One On The Last Night - S6-E6
Continuity mistake: At the end when Monica and Chandler hug, Monica's arms keep going from under to over Chandler's arms as the cameras switch many times. (00:20:00)
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.