The One with the Thumb - S1-E3
Continuity mistake: When Ross starts talking about his dog at the start of the episode, Monica has her left foot on the floor and she is holding onto her right leg. As Ross says 'send' both of her feet are on the sofa and her hand is between her legs. (00:01:00)
The One With The Cake - S10-E4
Continuity mistake: Phoebe's robot in the toy race is behind Joey's. Joey then says unlucky and picks his toy up. Phoebe then picks hers up and it is about a metre in front of Joey's. The toy can't move that fast. (00:16:40)
The One with the Ick Factor - S1-E22
Visible crew/equipment: When Rachel is telling everybody about the dream she had with her, Chandler and Joey in it, Ross stands up and starts talking. When he does, the stage lights are visible in the TV. (00:13:40)
The One With Rachel's Crush - S4-E13
Visible crew/equipment: When Rachel comes in at the start of the episode a stage light is reflected in the TV. (00:02:05)
The One With Chandler's Dad - S7-E22
Continuity mistake: When Monica and Chandler are in Vegas waiting for the show to start, Monica's wrap goes from high up on her shoulders to half way down her upper arms between shots. This happens more than once. (00:12:40)
The One With The Dollhouse - S3-E20
Continuity mistake: After Joey walks away from the understudy and sits at the table, his hands are on the table but not touching; they are touching in the next shot. (00:07:50)
Factual error: When the gang all see the beach house for the first time, it's covered in a layer of sand, which is supposedly left over from a recent flood. Well, if there really had been a flood, there would have been mold on the walls and debris or junk from the outside, and the sand wouldn't have been nice and clean and dry; it would have been moldy. And there would've been a pattern, likely on the walls, of where the water rose up to and where it receded. Not only that, but how did it get in? All of the doors and windows are intact. (00:04:40)
The One With the Sharks - S9-E4
Continuity mistake: When Chandler and Monica are talking about Chandler's shark obsession, his arms keep changing with each shot. When the shot is from behind (facing Monica) they are on the couch, and when the shot is in front (facing Chandler), his arms are folded in front of him. (00:19:35)
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 with the Thumb - S1-E3
Continuity mistake: After Chandler shouts at everyone because they are complaining about his smoking, there is an awkward silence and we see a shot of Rachel leaning on the sofa with her arms spread. In the next shot she isn't leaning on the sofa anymore. (00:14:25)
The One Where Monica and Richard Are Just Friends - S3-E13
Continuity mistake: When Monica is in Richard's room she lights candles then realises Richard's home with another woman so blows out the candles but misses one. Next she hides under the duvet waiting for Richard. When he comes in all candles are unlit but she is still under the bed. (00:18:00)
The One With The Ballroom Dancing - S4-E4
Other mistake: In the scene where Rachel is going to take out the trash, Monica tells her the garbage room is the 3rd door on the left. However, when Rachel comes back with the pizza box and Monica leaves for the garbage room, she leaves the apartment and walks towards the right - there are no doors that way, just the stairs. (00:00:50)
The One Where Ross And Rachel Take A Break - S3-E15
Continuity mistake: When Phoebe and Monica are at Monica's table and Phoebe is trying to convince Monica to go on a date with her date's translator, watch Phoebe's arm. She points at Monica when she says, "Don't call him that; his name is Spackleback Larry", but when the shot changes to a side view of them, she has her arm resting on the table with no time to put it down between shots. (00:06:25)
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 With The Chicken Pox - S2-E23
Continuity mistake: When Monica says about her boyfriend not having a 'Thing' her arms change place depending on the shot. (00:14:10)
The One with the Boobies - S1-E13
Continuity mistake: When Joey finds out that his mother knows about his dad's affair, she tells him she's fine and holds her hands to her chest. In the next shot her hands are outstretched in front of her. (00:17:10)
The One With The Ball - S5-E21
Visible crew/equipment: A stage light can be seen above Ross when he asks Rachel how much she paid for her cat. (00:04:05)
The One With Chandler In A Box - S4-E8
Continuity mistake: In the scene were Phoebe is calling for Monica's eye doctor, in the background you can see the TV is off. Then Phoebe asks if she wants to see the on call doctor, Monica says yes, and in the background the TV is on. (00:03:55)
The One Where Rachel Tells... - S8-E3
Continuity mistake: In the deleted scene on the DVDs Chandler is leaving the security interview with his holdall over his shoulder by the short strap. The camera cuts to outside the room and the holdall is now level with his legs. (Mistakes in Deleted scenes are valid if they are only in that scene which this is.) (00:24:50)
The One Where Rachel Tells... - S8-E3
Continuity mistake: In the deleted scene on the DVD, Chandler puts his plane tickets in his shirt pocket. Next shot the tickets have reversed. Look at the blue section. (Mistakes in deleted scenes are allowed if they are in that scene.) (00:25:00)
Answer: The painting doesn't have a name, and if it does it is never mentioned in this episode.