The One With Joey's Award - S7-E18
Visible crew/equipment: When Monica and Chandler are talking in the living room, Monica asks if there is 'anything you'd like to talk about, or share.' On the left of the screen the shadow of a boom mic can be seen moving on the lounge cushion. (00:17:20)
The One Where Rachel Has a Baby, part 2 - S8-E24
Continuity mistake: When Phoebe and Ross are standing in front of the screen looking at all the babies and talking about why He and Rachel aren't together, some of Phoebe's hair is in front of her shoulder on the right hand side then the shot changes looking over Phoebe's shoulder at Ross. Then when you see Phoebe again her hair is behind her shoulder yet she has not moved or touched her hair. (00:45:00)
The One With The Tiny T-Shirt - S3-E19
Continuity mistake: When Mark is telling Rachel they should get back at Ross right there on the couch, Rachel's hands go in a instant from on her chest to down her sides. (00:14:50)
The One With The Metaphorical Tunnel - S3-E4
Continuity mistake: When Rachel and Monica are comforting Chandler, just before he gets up Rachel has her hands on the chair but when Chandler gets up Rachel's hands change position. (00:12:40)
The One with the Monkey - S1-E10
Continuity mistake: Just after Chandler explains the situation to Janice, she goes off crying, and Ross takes a photo. The flash is much brighter than it should be - the screen's whited out to disguise a jump cut - after the flash Chandler's noticeably further back than he was before. (00:17:45)
The One with George Stephanopoulos - S1-E4
Continuity mistake: When Rachel explains to her friends about her job, for the first half of the scene there is a cushion behind her back. When Rachel says, "This is what I'm doing now, I've got this job." The cushion disappears. (00:07:40)
The One Where Everybody Finds Out - S5-E14
Continuity mistake: The amount of buttons undone on Pheobe's top by Joey changes after she says, "You didn't rip any buttons." The camera cuts to Joey then back, and it has changed. (00:18:00)
The One Where No One Proposes - S9-E1
Revealing mistake: When the nurse hands Emma to Rachel, you can tell it's not a real baby. (00:08:10)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: In one of Monica's flashbacks, her hands move between shots with no time to do so. (00:10:50)
The One With Christmas in Tulsa - S9-E10
Continuity mistake: After Chandler says "Merry Christmas" to the gang, they all respond - Phoebe just goes "blargh blargh", and has her hands in her lap. They all turn to look at her, and suddenly her hands are resting on the sides of the stool. (00:10:30)
The One With All The Kissing - S5-E2
Continuity mistake: In the Central Perk scene where Rachel is telling Ross she loves him, Ross is sitting at the small round table. The blue cup and the white cup with the lid move positions throughout the scene. (00:16:25)
The One Where Ross Moves In - S5-E7
Continuity mistake: At the very start of the episode, when Joey's showing Chandler National Geographic, Chandler has his left hand up by his face in one shot, then when the angle changes they're both clasped in his lap. (00:00:05)
The One Where Paul's The Man - S6-E22
Continuity mistake: When we hear the recording of Chandler answering the phone, it sounds nothing like what Chandler actually said. (00:13:00)
The One With The Proposal, part 2 - S6-E25
Visible crew/equipment: When Chandler walks in and sees Monica, the boom mic is visible above Monica's head. (00:17:45)
The One With All The Haste - S4-E19
Revealing mistake: When they are using cards to bet on the Knicks tickets, watch Joey carefully as he goes to reshuffle the pack from behind the arm of the chair. It's obvious that there are two decks, and he is in fact switching them over. (00:13:40)
The One Where the Monkey Gets Away - S1-E19
Continuity mistake: When Rachel tells Ross that she lost Marcel, the bottle of wine has the cork sticking half way out. In the next scene which continues directly on from before as Ross and Rachel argue, the cork is back in the bottle. (00:10:15)
The One With The Blind Dates - S9-E14
Visible crew/equipment: At the start in the coffee shop there are some stage lights visible in the coffee pot behind Joey. (00:00:05)
The One Where Rachel Has a Baby, part 1 - S8-E23
Continuity mistake: At the beginning, when Rachel first arrives at the hospital, she is talking about the hospital not being out of rooms. She points to herself with her right hand saying 'What if I was the president?' Then when the shot changes to include Ross she is pointing to herself with her left hand, then it cuts back to just Rachel and she is using her right hand again. (00:01:25)
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 Monica Gets a Roommate - S1-E1
Other mistake: Ross is a paleontologist but is seen working with the display on early humans which would be more of a job for an anthropologist.
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.