Continuity mistake: Diane is looking at the picture Carla gave her. The shot changes and Diane is now looking straight ahead as she gives Carla the picture. (00:08:25)
How Do I Love Thee, Let Me Call You Back - S2-E10
Visible crew/equipment: The shadow of a boom mic can be seen at the top of the screen when Sam comes out of the office to see who is coming with him to the fight. (00:09:10)
Old Flames - S2-E7
Continuity mistake: When Diane walks in and asks where Sam is, there is a box on the bar. When she walks up to the bar the box has changed, then later changes back.
Old Flames - S2-E7
Continuity mistake: In the opening scene when Norm is talking and he says "we caught a little movie this afternoon," he starts to take a drink from his beer, the shot cuts to behind him and he is still drinking. Then the shot changes - his mug is sitting in front of him, and he starts to take a drink. (00:00:40)
Visible crew/equipment: When Carla is having her vision about Cliff the camera goes to a wide shot - at the top of screen you can see the shadow of a boom mic.
Get Your Kicks on Route 666 - S10-E2
Visible crew/equipment: The edge of the set can be seen after Norm drives up in the golf cart. (00:22:30)
Get Your Kicks on Route 666 - S10-E2
Revealing mistake: When the guys are stranded you can tell the background is just a backdrop as the scene is not perfectly flat - there are some wrinkles in it. (00:13:05)
Get Your Kicks on Route 666 - S10-E2
Continuity mistake: When Frasier is sitting at the bar talking about the trip he is going to take, Cliff walks over and sits down. There is a beer sitting in front of him - he pushes it forward and Sam moves it. The shot changes and the beer is back where Cliff had first moved it, and he is holding his own beer. For the rest of the scene his beer keeps appearing and disappearing while the other one keeps changing position.
Continuity mistake: When Sam puts the paper from John on the bar it is next to a bowl, the next time we see it there is now more space between the bowl and the paper. Part of the paper is in the air, then the next shot when Sam picks up the paper it is lying flat on the bar.
Visible crew/equipment: At the end of the episode when Cliff is talking you can see the end of the set, the brick wall changes to a curtain. (00:23:55)
Continuity mistake: When Claudia is saying goodbye to Sam she is holding her purse and a magazine, at first the purse is against her body, the shot changes and the magazine is.
Birth, Death, Love and Rice - S4-E1
Continuity mistake: When Cliff and Norm are walking from the pool room there is a beer on the counter. The shot changes and it disappears. Norm sits down and it reappears, only to disappear when the shot changes.
Continuity mistake: When Frasier and Sam are talking in Sam's office, Sam sits down in his chair and leans back, the shot changes and he leans back again. (00:07:15)
Behind Every Great Man - S3-E19
Continuity mistake: When Paula first comes into the bar the amount of beer in Norm's mug keeps changing.
The Mail Goes to Jail - S3-E17
Continuity mistake: The first time Sam leans down when Diane is stuck in the vent, in the closeup shots of Diane, Sam's glove is missing from his hand on the floor.
The Heart is a Lonely Snipe Hunter - S3-E14
Continuity mistake: When the guys get back from snipe hunting Norm puts his hat on the bar. The hat changes position a few times throughout the scene.
The Heart is a Lonely Snipe Hunter - S3-E14
Continuity mistake: When the guys are getting ready to leave for fishing and Diane is trying to get them to take Frasier, there is a carton of half and half on the bar. At one point Diane is seen taking it and holding it, but a couple of shots later the carton is now back where it was.
The Norm Who Came in from the Cold - S10-E4
Continuity mistake: Carla tosses Rebecca an egg she is supposed to take care of, like a baby, for a $5 wager. The egg bounces off Rebecca's hands and over the bar onto the floor. In the next scene, Lilith and Frasier are walking into the bar and the egg was shown as being smashed on the bar itself. The next cutaway, with Lilith walking by the same spot, has no egg on the bar anymore. (00:03:40)
One for the Road (1) - S11-E26
Continuity mistake: After Don leaves the bar, a few minutes later Frasier shouts at him, "Run, Don! Run like the wind!" and Rebecca is left sitting alone at the table crying, but when it cuts to the overhead shot of the bar we see Don is still sitting at the table, even though he left five minutes earlier. (00:07:05 - 00:08:15)
One for the Road (1) - S11-E26
Visible crew/equipment: When Rebecca leaves Don at the table to relax while she gets champagne to "celebrate the answer", it cuts to an overhead shot as we hear the TV host introduce Salman Rushdie and Dr. Ruth, and the set lighting can be seen as well as the boom and mic moving around at the top of the screen. A few minutes later the mic can be seen bobbing again in the overhead shot from the same angle. (00:03:20 - 00:08:20)
Answer: Here is the source of the "WE WIN" photo: http://www.oldnycphotos.com/nyny587ac.html Brooklyn, of all places.