State and Main (2000)

Continuity mistake: William H. Macy makes dinner plans with the Mayor and writes "Dinner with the Mayor" on the dry erase board in his office. He writes "Dinner w/ the Mayor" in the "Tuesday" slot. Then an intern comes in and accidentally wipes the appointment off the board with her shirt. Macy yells at her and tells her to rewrite the appointment on the board. The whole premise of the joke and pretty big part of the movie is that the intern rewrites the appointment in the wrong day, thereby causing the Hollywood people to miss dinner, enrage the Mayor and his wife and have the town turn on them. When the girl walks away however, the appointment is clearly rewritten in the correct day (Tuesday). This ruins the whole misunderstanding because although the appointment is in the wrong day later in the movie, at the moment the joke is supposed to be set in motion, there is no mistake.

Continuity mistake: Joe and Annie are running in the rain to her shop and they pass Bucky, the firehouse dog at the firehouse. Joe and Annie go into her shop and you can clearly hear Joe firmly close the door. Shortly after, they are about to kiss and Bucky jumps up between them. They take him outside and the door closes behind them, locking them outside. If the door automatically locks when it closes, how did Bucky get inside in the first place?

Revealing mistake: Joseph White is having his glasses fixed by Ann. Ann asks a local passer by for some fishing line from her fishing kit. As the glasses are being fixed Joseph gets a fishing hook stuck in his finger. At first we see the hook embedded in his finger, but in the next cut we see Joseph showing the finger and hook to Ann. You can see that the line and hook are tied around his finger.

Bob Barrenger: Only second chance I know, is the chance to make the same mistake twice.

Tommy Max: My wife is going to have a baby.
Walt Price: Oh, good, let's bring more people into this overcrowded world.

Walt Price: How are we coming with the dead horse scene?
Marty Rossen: You can't actually kill the horse.
Walt Price: Aw, fuck me.