Corrected entry: When Fry and Leela go into Robot Hell, Nibbler leads the way. But when Bender rescues them and they fly away with him and his angel wings, Nibbler is not there - They've forgotten him. However, sure enough, he's back next episode.
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.