Other mistake: The Monster appearing in the pilot and causing the turbine to explode is a mistake (not trivia). This is actually an artefact of poor CGI effects that was left in the show in error. It was confirmed by the producers. You can see it best here: http://www.lostpedia.com/wiki/Image:Turbine_Explosion.gif.
My Master, the Weakling - S3-E5
Other mistake: About 3 minutes into the show, Don Rickles goes around a corner to get some equipment but you can see his left arm at the corner while he's waiting for his spot to come back into the scene.
Other mistake: During the Vagina Monologues show, the pair of legs casts a shadow but the microphone stand doesn't. (00:00:45)
Other mistake: Lois digs up Chloe's grave site to unearth her casket. It is obvious that the casket is not buried six feet deep. You would think, with all that is going on, that LuthorCorp would have at least buried the casket deeper to deter inquisitive eyes and maybe throw in a few scattered bones for good measure.
Other mistake: When the kids are playing "Carry On Wayward Son," there are no notes on the TV in the one area. However the boys play the notes there and get it right.
Other mistake: Gus is talking to his employee about the twins while writing something on a clipboard. However, he is using the opposite end of the pen and just pretending to write. (00:14:40)
Other mistake: Throughout the episode, including the very first shot, we see the sun is shining brighter and hotter than usual. This lends credibility to the theory that Superman's powers are responsible for increased solar activity. Later on in the episode it is revealed that the heatwave is being orchestrated by Lex Luthor, who is is heating an underground river to coincide with Superman using his powers. Lex does not however have any control of the weather, and no explanation is offered for why the weather conveniently 'played along' with his plan.
Other mistake: The battle droids - including the commando droids featured here - habitually have two broad fingers and a thumb. So how can a commando droid squeeze itself completely into clone trooper armor without its broad fingers tearing open the gloves, since it can't separate its fingers?
Other mistake: When Azula attacks The Western Air Temple, there is a close up shot of her when she says that she is about to become an only child. Pay attention to the smoke coming from the airship behind her, especially above her head: it doesn't move. Even if this was remotely possible, it does move when the camera zooms out, making it a mistake nonetheless.
Other mistake: During the battle near the end of the episode, Sisko is heard saying, "Locking onto the lead ship" but he gives the firing order to Bashir, who is seated at the helm. This implies that the targeting controls and firing controls are at separate stations, which makes no sense.
Episode #1.1 - S1-E1
Other mistake: When detective Campbell is making his speech to the officers, the board behind him has dates ranging from 1966 - 1975.
Other mistake: Leonard says he had a growth spurt after his high school prom. In "The Cooper-Hofstadter Polarization" he told Penny that he still had all his clothes he owned since the eighth grade, after his last growth spurt.
Other mistake: When O'Neill first goes to visit Teal'c in his cell the symbol of Apophis on Teal'c's head is upside down.
Other mistake: When the train stops Godfrey gets off to relieve himself but when he is climbing back in to the carriage the train appears to be already moving at speed because the background projection started moving too early.
Stephanie Plays the Field - S4-E22
Other mistake: It looks like she has earring holes. Didn't she get her ears pierced later on in the series?
A Quiet Day in Dodge - S18-E19
Other mistake: Festus returns from catfish fishing carrying a gunny sack full of fish that is bone dry when it should be dripping wet or at the minimum damp from the fish.
Other mistake: When Rob dials the radio station, he dials the phone number and then looks it up in the phone book. He covers for himself, and then has a hard time keeping a straight face afterwards.
Suggested correction: The part is Rob checking to see if he had the right number.
Marco Polo - S1-E4
Other mistake: In episode seven, Kublai Khan refers to backgammon as a game of cards....obviously he's not an experienced backgammon player.
Other mistake: When Billie visited Georgia's grave in Salem, she acted as if the baby was buried there, yet, Billie should know that the coffin buried is just a bunch of rocks and the real Georgia is buried where Earl, Wayne, and their mother live by the bayou. Billie lied to Bo about Hope being the cause of their baby's death and buried the rocks in the coffin to make it look like the baby had died after her fight with Hope, rather than before.
Other mistake: The tenant board member tells George that Mr. Eldrige in apartment 8C has decided he wants the new apartment. However, the new apartment in question has a 3-digit number - 808 I believe. This indicates that the building would not have single digit numbers and letters (Such as 5E, 8C, etc.) as part of its numbering system.