Revealing mistake: When Grace and Will are looking at the large tin of Protein shake powder, you can see there is tape covering all of the logos and brand name on the tin. (00:21:45)
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)
Revealing mistake: When Grace is getting out the Board Games for her and Karen to play, the names of the Board Games have been covered with strips of tape. (00:53:00)
Alley Cats - S1-E21
Revealing mistake: When Will goes to pour himself a glass of whiskey, the brown liquid that is chosen to represent the liquor has foam bubbles on the top of it that resemble the ones that soda has.
Guess Who's Not Coming to Dinner - S2-E1
Revealing mistake: When Will is supposedly naked, reading his book, you can see he is wearing underwear when he slams the book down as Grace leaves. (00:08:30)
Acting Out - S2-E14
Revealing mistake: When Will is talking to Jack outside of NBC, you can see the hired security they used to film on the street. They are two big men in black leather coats walking either side of them. (00:00:50)
Acting Out - S2-E14
Revealing mistake: As Will and Jack walk along the street, out of NBC, they stop and Will says "Once you have a weatherman on your sideĀ ." you can see people across the street staring at the crew and actors, and one man even takes a photo. (00:16:55)
Hey La, Hey La, My Ex-Boyfriend's Back - S2-E16
Revealing mistake: When Grace is unpacking her groceries, you can see some brand names have been covered up with black tape.
Revealing mistake: After the opening credits there is a shot showing the house on the island where Karen and Stan live. If you look at the hanging chair, you can see that Karen is sitting in it. But in the very next shot she is in a meeting with Will, in a different outfit. This is a re-used shot from the previous season, which shouldn't be there. (00:04:20)
Lows in the Mid-Eighties (1) - S3-E8
Revealing mistake: At the party it is obvious none of the red plastic cups have drink in them. (00:45:00)
Three's a Crowd, Six is a Freak Show - S3-E10
Revealing mistake: Grace's boyfriend has six toes but in closeup shots, when he takes off both socks you can clearly see only five toes on each foot, when they are specifically trying to hide one foot.
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)
Mad Dogs and Average Men - S3-E18
Revealing mistake: When Grace eats the dog food from the frying pan, we hear the sound of it sizzling, but we see no steam coming from the food. (00:09:05)
Poker? I Don't even Like Her - S3-E19
Revealing mistake: Karen clearly doesn't suck any air from the balloon (that's why her voice doesn't go high.) (00:33:55)
Prison Blues - S4-E4
Revealing mistake: When we see Grace rolling down the staircase, when she hits the wall, it gives in, like a cheap set wall. (01:22:10)
...And the Horse He Rode in On - S5-E1
Revealing mistake: At the beginning of the episode, Grace is running through the park, and she unexpectedly runs right into a lamppost. When she hits the lamppost, the lamppost shakes very violently, like a cheap set lamppost.
Revealing mistake: Will is reading a book in the total nude on the sofa, and then Leo walks in on him. When Will gets up from the sofa to run into the bathroom, you can blatantly see pants around his waist as he gets up from the sofa and runs to the bathroom.
Revealing mistake: When Grace plays on the Dance Dance Revolution machine in the arcade, at the bottom of the game screen it reveals that it is a demo, and also says "Free Play."
Revealing mistake: When Grace steps on the Dance Dance Revolution machine, she positions herself in a way it looks like she's playing on Double Mode, but the on-screen arrows in the game clearly show that she's playing on Single Mode.
Answer: A history of the game can be found at http://www.fast-rewind.com/bacon.htm.
J I Cohen