Continuity mistake: When Peter launches himself off a firework into Cleveland's house he hits the top floor and completely misses the ground floor. Yet the entire house is damaged including the ground floor. (00:01:25)
Visible crew/equipment: When Dianne's daughters have locked themselves alone in the room, just as Jerry is about to put the keys in the door to unlock it so they can prevent the girls from cutting their hair, the boom microphone dips into view in the room where the girls are alone. This boom mic is not from the "documentary" crew. (00:13:25)
Continuity mistake: While Axl's in Sue's dorm room when she's getting ready to leave, Sue puts one of the backpack straps over her shoulder, then in the following shots it goes back and forth between having only one or both straps over her shoulders.
Alternative History of the German Invasion - S4-E4
Continuity mistake: When Malcolm McDowell is writing on the board early in the episode, he draws a line under the word "victors". In the next shot of the board, the line has moved, and the gap between the V and I is larger.
Revealing mistake: While the ODIN agents are hallucinating, one can be seen looking into the barrel end of an MP40. If you follow him as the scene continues, the gun clips out of the sprite's visible area, and is almost entirely gone. (00:14:30)
Continuity mistake: After the officers show up in Kim's office regarding the kidnapping, in the closeup one of them uses his left hand to contact Control via his shoulder mic, but in the next wideshot it's his right hand up at the radio mic.
Continuity mistake: Tara is sitting at her desk and tells Max they will have sex the following night, and she teases him that she "Might even bring some props." Right as she says this line, the camera cuts. In the first shot, she has one pencil in each hand, but in the second shot, suddenly both pencils are in her left hand. The position of her hands changes between cuts as well.
Something Fishy This Way Comes - S4-E13
Continuity mistake: When Dmitry and Hank are talking while waiting for Amir to return, Boris approaches Dmitry and hands him a drink. The drink is initially in Dmitry's left hand, but when the shot cuts, the drink has jumped to his right hand. (00:26:35)
Continuity mistake: When Burke receives his new watch from Elizabeth, it is totally different to the one he wears when interviewing the dress designer later. (00:18:44 - 00:25:29)