When Juliet comes in to talk to Jack, Miles and Hurley are sitting on the couch playing Mahjong with two glasses of juice in front of them. When they get up to leave, the glass in front of Miles is suddenly gone.
Kate tells Jack it is "their" fault Sayid shot Ben, because "they" brought him to the island. Sayid was on the flight because of Ilana, he wasn't going back.
When Kate is donating blood for Ben, she is sitting on a table, leg propped up on a chair. In reality, during blood donations the donor always lies down on a bed, to prevent their blood pressure dropping.
At four minutes in, Kate is operating the winch, along with Roger Linus, who is pulling out the VW van that crashed and burned in a Dharma home. When Roger says "whoa, that's good right there" telling Kate to halt the winch, the tow line was already on the ground. It wasn't taut.
When the Others ambush Sawyer and Kate, each raising of a rifle is accompanied by a racking sound, although only few of them actually rack their rifle. It would be illogical anyway to wait with loading the first round into the chamber until raising the weapon. The racking sounds are only added for dramatic purposes.
When Kate takes Aaron into the grocery store to get him a drink, there's a logo for Times Supermarket on the wall. Times Supermarket is found only in Hawaii. They're supposed to be in Los Angeles.
Kate goes to Cassidy's house in Los Angeles to give her money from Sawyer. However there is a street sign that says Lumi'Au'Au which means it was shot in Hawaii.
Horace asks Jack for his name, despite the fact that Jack has his name embroidered on his jumpsuit.