Corrected entry: At the planet with the Slurm, when they first meet Slurms MacKenzie, Fry gets some goo on his hand. He wipes it off on his pants and when he is doing so, the goo just disappears from picture. (It doesn't even fade a little).
As the power builds up in Bender, his left eye pops out, making him a cyclops, subsequently being eaten by the Cyclops eater. After the monster dies, Bender comes out, and has two eyes in the long shot, but puts his left eye back in the close up.