At the opening scene when Howard is flirting with Penny while Leonard is distributing food, right after Howard says "creepy good or creepy bad", he suddenly is holding his shrimp box before Leonard hands over to him.
Just after Wolowitz makes the 'Apu from the Kwik-E-Mart' joke, Leonard walks to the kitchen and starts unpacking the takeaway. He first takes out 2 portion cups, then in the next shot he takes out 2 more. However, this results in there being only 3 portion cups on the table.
When Sheldon sets the container of baby wipes on the table, the direction it faces keeps changing (most noticeable by the direction the open cap points.)
When the guys are eating Chinese food, the second time. Leonard and Howard's Chinese cartons changes in their hands, periodically throughout the scene.
After Raj hangs up his phone at dinner, he sets it on the table, with his right hand, near his left arm. It then cuts to a 1.75-second shot of Leonard, then back to Raj and he holds his drink in his right hand and the phone sits near it. Later, while talking to Sheldon, the level of liquid in his glass lowers itself without him drinking any.