Visible crew/equipment: After Ross and Rachel cover the table with the sheet, when Phoebe walks in Rachel says they can turn out the lights and watch the movie, and in the next shot we can see the end of the set wall, the soundstage and a crewmember's leg.
Visible crew/equipment: After Charles confronts Choi Sung Ho about the candy, Ho explains that he sold it on the black market to buy real food, and when Ho reenters the mess tent through the side door, we can see that outside there's a director's chair, which actors also use, with something printed on its back.
Visible crew/equipment: When Dewey yells for Lois because the bow was put on the present, if you look to the left of Lois, you will see a crewmember kneeling down, handing Lois the Red Dress, who is holding a bucket of water. He quickly gets out of the camera's view. [This is on the DVD of the first season. Someone said on the audio commentary that after catching it, they deliberately left it in to see if anyone would spot it. It's still a mistake, but that's why it's there.]
Visible crew/equipment: At the beginning of the episode, Jeannie is talking on the phone by the stairs and her sister is hiding behind the banister. Her sister stands up for a moment and shows her full face, revealing that it is actually Barbara Eden's stand-in wearing the green costume.
Visible crew/equipment: In the beginning of the episode, Joey is preparing the game with Michelle and the team. When Joey asks if anyone has any questions, Aaron says he does and asks Joey if after the game he was going to buy them pizza or if he was too cheap. Right when the shot changes to Joey, you can see for a brief second at the top left hand corner that the mic is visible and a camera on the bottom left.