Vixen said:
Nobody doesn't like Molton Boron

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I don't really have a favourite episode, but my favourite line is in Crimes of the Hot, when Bender is leaving and Fry tries to stop him:
Fry - "We'll pile fruit on you and claim you're a bowl" <places Bananas on Benders head> "I won't let you!"
From the same episode.
Farnsworth : One million robot lives are about to be destroyed. The Jedi's are going to feel this one.
Cant pick one fave episode but some that stick out
The Deep South
'We cant swallow those'
'Then good news! Its a suppository'
Anthology of Interest
'You watched it. You cant un-watch it!'
Insane in the Mainframe
'I'm going to remind Fry of his humanity, the way only a woman can.'
'You're going to do his laundry? '
Time Just Keeps on Slipping
'At this rate, by Tuesday it'll be Thrusday, by Wednesday it'll be August, and by Thursday it'll be the end of existence as we know it! '
Teenage Mutant Leela's Hurdles
'Driving gloves, driving goggles, driving thong. There!'
'Uh, maybe I should drive'
'Hehe, you? A woman? I'm trying to catch a monster, not find the quickest route to the mall!'
The Devils Hands are Idle Playthings (Actually probably my fave)
'Your lyrics lack subtlety. You can't just have your characters announce how they feel! That makes me feel angry!'
And special mention to Brannigans best episode
Amazon Women in The Mood
'You win again, gravity!'