Couch Gag: In a backwards parody of The Wizard of Oz, The Simpsons (in their colorful world) are sucked up by a tornado and put on a farmland shown in black and white.

Chalkboard: There's no such month as "Rocktober"

(Bart marvels at the things in Simon's bedroom)
Bart: Wow, cool poster of Joe Montana.
Joe Montana: (steps out of the wall) It's not a poster.
(Bart screams)
Joe Montana: I'm the real deal. Every day I stand here the family donates a million dollars to Notre Dame. Did you know the words "Notre Dame" are French, but the team is the Fighting Irish? That's the kind of thing I think about in here.
Bart: Back in the poster, gabby.
Joe Montana: Yes, sir.

Homer: You just cost me $200,000!
Bart: I thought it was 50.
Homer: I was gonna bet it on the dogs!

(Chief Wiggum takes care of the robot vacuum cleaners gone wild)
Chief Wiggum: These innocent robots-- (shoots one) --couldn't have done this on their own-- (shoots another) --someone would have to turn them all on at once-- (shoots another) --and then set them on some kind of malevolent sentience.
(Picks one up and examines a switch that reads "On", "Off" and "Malevolent Sentience" with the switch turned to the latter)
Chief Wiggum: Yep, there it is.

This episode's title is an adaptation of 'Double Double Toil & Trouble', a line said by the Witches in William Shakespeare's 'Macbeth'