Continuity mistake: When Karen is laying on bed, looking at the leaflet Jack gave her, between shots her martini swaps from her left to her right hand. (00:26:40)
Tea and a Total Lack of Sympathy - S2-E10
Continuity mistake: When Karen is in Will's office near the end, telling him why she signed the papers, she holds a black handbag in her right hand. When she says "what's that?" the handbag is hanging over her left arm. (00:40:45)
Continuity mistake: Grace puts the coffee pot down twice after pouring Will a cup, as he and Jack talk about Claire. (00:23:05)
Continuity mistake: During the thanksgiving dinner, Will is mixing salad. He then leaves the mixing spoons in the bowl. In the next shot they've vanished, and then reappear later on in the scene, back in the bowl. (01:14:00 - 01:15:35)
There but for the Grace of Grace - S2-E21
Continuity mistake: When Ben is mixing the salad with Karen, Karen walks away, and one of the wooden spoons they were mixing with falls onto the worktop. In a following shot the spoon has suddenly jumped back into the bowl so that there are two in the bowl, then in a later shot the spoon vanishes once again. (00:54:25)
There but for the Grace of Grace - S2-E21
Continuity mistake: When Shannon is asking Grace why she didn't go through with her marriage, there are three glasses of near-empty wine on the table. In one shot they all completely vanish, then reappear in the next shot. (00:55:40)
Acting Out - S2-E14
Continuity mistake: Jack's scarf keeps changing position as he is riding his bike alongside Will and Grace, down the street. The scarf repeatedly alternates from behind/in front of his shoulder. (00:00:35)
There but for the Grace of Grace - S2-E21
Continuity mistake: When Will and Grace are sitting at the dining table discussing how much like Sharon and Joseph they are, the napkins on the table change shape and move around a bit, and one ends up with a plate underneath it just before Will picks it up.
Continuity mistake: The art show is supposed to take place at the Zelman gallery and inside there is a sign that says that, but the establishing shot shows that the name is the Phyllis Kind gallery.
Answer: A history of the game can be found at http://www.fast-rewind.com/bacon.htm.
J I Cohen