The One With Rachel's Date - S8-E5
Visible crew/equipment: When Chandler tells Bob "it's his fault", there is a bin behind him that reflects the stage lights. (00:16:10)
The One With Rachel's Date - S8-E5
Visible crew/equipment: As Phoebe walks into the restaurant kitchen, a crewmember's hand is visible stopping the door from swinging too much. (00:16:50)
The One With Rachel's Date - S8-E5
Visible crew/equipment: When Ross shows up at Chandler's office and they both head out to go to the Hard Rock Cafe, just as Chandler walks out the door we can see the edge of the right wall set, allowing us to see the hallway Chandler just walked into and even Chandler's arm.
The One With Rachel's Date - S8-E5
Visible crew/equipment: While Phoebe and Tim are at Central Perk, when Tim's beeper goes off he blows Phoebe a kiss when he leaves, and as Phoebe catches that kiss and throws it away have a look at the left side of the screen, where the Central Perk wall ends we can see part of Monica's restaurant kitchen set - the door and the wall beside it. (Widescreen version).
The One With The Halloween Party - S8-E6
Visible crew/equipment: Right after Joey has finished his impersonation of Chandler, kids can be heard knocking on the door. When the camera pans to Rachel, stage lights can be seen in the top right-hand side of the screen. (00:05:15)
The One With The Stain - S8-E7
Visible crew/equipment: When Brenda is cleaning the top of the cabinets, stage lights can be seen on the top right-hand corner of the screen. (00:11:45)
The One With Monica's Boots - S8-E10
Visible crew/equipment: When Chandler is giving Monica a piggy-back, Monica sees her boots in tan in the store window. In the non-widescreen version, the cameraman can be seen in the reflection of the glass. This was fixed in the widescreen version. (00:17:45)
The One With Monica's Boots - S8-E10
Visible crew/equipment: When Joey is talking to Bobby and Dina, lights and a boom mike can be seen at the top of the screen. (00:18:40)
The One Where Joey Dates Rachel - S8-E12
Visible crew/equipment: As Ross enters the classroom for his second lesson, he bursts in and for roughly five seconds, a boom mic is visible hovering overhead near the door. (00:10:15)
The One Where Joey Dates Rachel - S8-E12
Visible crew/equipment: In the scene of the classroom, before Ross faints, he says, "Why don't you all" and above his head near the clock, there is a boom mic. (00:18:50)
The One Where Joey Dates Rachel - S8-E12
Visible crew/equipment: When Ross is wearing roller-blades while teaching his class, just as he points to the map and says, "Here," the second time, there's a hidden crew member that can be seen behind the end of the set wall with the map, at the left side of the screen.
The One With The Secret Closet - S8-E14
Visible crew/equipment: When Chandler walk in Joey's apartment and say "Rachel's all moved out, huh?" as he walks towards Joey a lot of set lights are visible above their heads. (00:18:55)
The One With The Tea Leaves - S8-E17
Visible crew/equipment: After Monica and Chandler leave the apartment so Joey and Rachel can be alone, Rachel tells Joey that it's nothing and he tells her he's going to take-off, then in the next wideshot the camera can be seen at the left side of the screen. (00:08:30)
The One In Massapequa - S8-E18
Visible crew/equipment: After the anniversary party, when Rachel and Ross are back at the apartment and Ross tells her that it was the easiest four hundred bucks he ever made, Rachel gets up and just as she walks around the couch we can see the reflection of the cameraman/crew member in the mirror on the wall, at the right side of the screen.
The One With The Baby Shower - S8-E20
Visible crew/equipment: Monica chases after Rachel's Mom to apologise and she falls over and you can clearly see the safety mat move when Monica falls on to it - it's blue and just down the first step. (00:22:00)
The One With The Cooking Class - S8-E21
Visible crew/equipment: In The One With The Cooking Class, just after Ross gets back from his date, a boom mike is hovering over Rachel's head. (00:17:25)
The One With The Cooking Class - S8-E21
Visible crew/equipment: When Joey and Monica are leaving the cooking class, the teacher asks about the difference between hollandaise and béarnaise sauce, and in the next shot of Monica and Joey we can see the shadow of the moving boom mic at the top left side of the screen.
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 Has a Baby, part 1 - S8-E23
Visible crew/equipment: Right after Rachel says, "Do you know that feeling when you're trying to blow a Saint Bernard out your ass?" the camera cuts to a view of Monica and Chandler. Behind Monica and Chandler, part of the set is visible, along with a man on crutches.
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.
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.