The One With Ross's Grant - S10-E6
Continuity mistake: When Aisha Tyler and Greg Kinnear put one hand on Ross's face, they bring those hands together and they interlock fingers, then the camera changes positions and they interlock fingers again. (00:22:20)
The One With Ross's Grant - S10-E6
Continuity mistake: When Monica comes round to Phoebe's, Phoebe reminds her that she's got to clear out stuff. In this wide shot Monica has both hands by her sides, but when it cuts to her finishing saying "oh right", her right hand is now gripping her bag's strap. (00:05:00)
The One With Ross's Grant - S10-E6
Continuity mistake: When Charlie and Benjamin are at the restaurant, Benjamin says "I can't believe you chose this restaurant. You remember that night?" To which Charlie replies "I can't believe they let us back in here." However in "The One With The Fertility Test" Charlie has never been to New York before.
The One With Ross's Grant - S10-E6
Continuity mistake: After Joey puts the video in the player, it's clear the video doesn't go all the way in, and even starts to eject itself. The shot cuts, and without him making any moves to replace the tape, it plays fine.
The One With Ross's Grant - S10-E6
Continuity mistake: When Phoebe tells Rachel and Monica that Mike lets her keep her box of hair, Rachel's chopsticks are down, by the plate. In the next shot, she's holding them close to her mouth.
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.