Continuity mistake: In the shot where the note from Leela's file gets ripped off, note the small tear on the note. Then in a later shot when Fry is showing the Professor the note the small tear has disappeared but then later on the small tear is back again.
Continuity mistake: As Bender is stomping to stuff the whale down the sewer, when the rope gets to the pavement, the top where the cover is tied suddenly jumps from the level of Bender's head to below the spot where his legs and body meet.
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.