Continuity mistake: When Will and Grace sit on the rocks in the meditation room, at the end of the episode, the position of Grace's coat changes between each shot. (01:22:00)
Whose Mom is It Anyway? - S2-E4
Continuity mistake: When Jack and Karen are waiting outside the INS office,Karen's leans against the back of the bench she is sitting on, and her arms are not crossed. When the shot changes, her arms are suddenly crossed. (00:12:15)
Whose Mom is It Anyway? - S2-E4
Continuity mistake: Near the beginning of the episode, Will is pouring some wine. First, he pours a full glass and hands it to Grace, then he begins to pour another glass that obviously already has wine in it. He then hands this to Grace and takes an empty glass from her to fill, which he already filled (there is no sign that she already drank the wine in the glass). (00:01:55)
Continuity mistake: After Will and Jack unwrap their breakfast Jack puts the wrapping that the Smart Start cereal box was wrapped in, on the table. In some shots during the rest of their conversation, the wrapping actually vanishes in some shots.
Three's a Crowd, Six is a Freak Show - S3-E10
Continuity mistake: When Grace gets two bottles of beer for her and Mark, she sits down on the sofa with both bottles in her hands, yet in the very next shot one of the bottles has jumped into Mark's hand.
Where There's a Will There's No Way - S1-E7
Revealing mistake: When Grace slams into the side of the elevator buttons, they all light up except 4 (which is supposed to happen), but 5 lights up after she moves away from the panel. (01:22:30)
Will on Ice - S1-E11
Continuity mistake: When Will and Grace play the "love her, hate him" game, they open a magazine up. In the next shot you can tell it's on a different page, because the layouts have changed. (00:05:45)
Boo! Humbug - S1-E5
Continuity mistake: When Will grabs the silly string from the table, he pulls off the yellow lid and drops it to the floor. In the next shot the lid is on the coffee table. It alternates from on the table/floor for a few following shots as well. (00:59:25)
Continuity mistake: When Will introduces Grace to April, the pencils in Grace's hair changes between shots.
Between a Rock and Harlan's Place - S1-E4
Continuity mistake: When Will and Grace are eating dinner, Will has his knife and fork in his hands, but in the very next closeup he his wine glass in his hand. (01:05:00)
Revealing mistake: Grace has a present for Larry and Joe - a cement handprint decorated with twigs. She made it when she was twelve, and after a couple of decades the twigs in the cement are stick alive with healthy green leaves. (00:30:50)
Visible crew/equipment: When Grace asks Will for his advice on where her mirror in her new apartment should go, she goes running to the wall and when she does, the camera pans over and you can see that the wall stops, revealing it to be a set.
Continuity mistake: When James Earl Jones puts his hat down on the piano, he puts it upside down. But in a later shot, as he tells Jack that he's fired, we can see the hat is now the right way up, behind Karen. Later it's upside down again. (00:18:25 - 00:19:25)
Continuity mistake: In the episode "23" when Lorraine, Karen and Will are talking in the entrance to the church, before Stan's funeral, there is a signing book with a pen laying on it. But in one shot the pen has jumped back into the pen holder. It's back to laying on the book in the following shots.
Bacon & Eggs - S5-E2
Continuity mistake: When Leo comes into Grace's design workplace, he starts to put pieces of cloth on his shoulder. Between shots, before Grace takes the pieces of cloth off of him, they change position on his shoulder completely.
To Serve and Disinfect - S2-E6
Continuity mistake: After Will and Grace finish eating the pizza on Will's desk, in his office, the positions of the napkins, pizza slices, pizza box and water bottles keeps changing throughout the scene. (00:42:35)
Visible crew/equipment: In Grace's bedroom, when Will says "c'mere you" to Jack, Jack runs over, and then Will pushes him out of the door. However, as Jack is running to Will, you can see the boom mike above them. (00:48:00)
Continuity mistake: After Will squirts his bottle of water all over Jack, the amount of water on his shirt and face differs through following shots. (00:10:00)
Answer: A history of the game can be found at http://www.fast-rewind.com/bacon.htm.
J I Cohen