SpongeBob is taking Gary for a walk. They spot Mr. Krabs in a free parking spot. Gary gets a little spazzy, so Mr. Krabs asks what's wrong. SpongeBob says that's what Gary does when he finds money. Mr. Krabs decides to take Gary to look for spare change all around town to feed his obsession for money. When SpongeBob asks what Mr. Krabs is doing with Gary, he just gives SpongeBob an impossible task (like painting the Krusty Krab with a toothbrush, or rearranging all the wall rivets from largest to smallest).
Mr. Krabs collects money from people at the Krusty Krab, Goo Lagoon, and the Laundromat. He then finds an arcade and goes inside. Mr. Krabs decides to disguise himself and Gary as a pregnant woman. Mr. Krabs tries to take everyone's money, but Gary is so worn out that he can't attract money anymore, as doing so causes him pain. Meanwhile, SpongeBob is finished with his tasks, so he looks for Mr. Krabs, but the guy Mr. Krabs took money from tells SpongeBob that Mr. Krabs and "his snail" have been stealing money. SpongeBob finds Mr. Krabs and is mad at him for putting Gary through all that pain just for money. They begin to argue, but they get distracted as Gary involuntarily starts collecting all of the money in the arcade (even from inside the game machines themselves!) The huge amount of money forms a massive wave of coins, which begin sliding towards all the Bikini Bottomites in an avalanche sort of fashion.
Everyone tries to exit the arcade to avoid being swept away, except for Mr. Krabs, who runs toward the large wave of coins in a fit of money madness and gets literally crushed by them. Mr. Krabs ends up in the hospital. After discussing what happened to Mr. Krabs, SpongeBob asks what caused Gary to begin attracting money. The doctor discovers that he had swallowed SpongeBob's Mermaid Man and Barnacle Boy fridge magnet, which had quite a strong magnetic pull. When the doctor points out the bill to Mr. Krabs, he responds that he doesn't have enough money to make his payment. The doctor corrects him by mentioning that all the change he collected with Gary would cover it, prompting Mr. Krabs to yell "Nooooooooooo!" in defeat as the episode ends.
( ‣ ) Associated production music
( • ) Original music
( ◦ ) SpongeBob music
‣SpongeBob Theme - Jeremy Wakefield, Sage Guyton [title card] ‣Dachshund Walk - John Fox, Mac Prindy [SpongeBob taking Gary for a walk] • ? - Nicolas Carr ["Mr. Krabs?"] ‣Cartoon Sting 3 - Gerhard Narholz ["What's happening to your critter there?"] ‣Sailor's Sting 4 - Michael Bolger, Nicolas Carr [Gary attracting coins] ‣Animal Antics - Phillip Green [Gary attracting other people's change] ‣Drama Link (d) - Hubert Clifford ["Close up?!"] • ? - Michael Bolger, Nicolas Carr ["You haven't de-greased the fryer."] ‣ ? [Krabs at the beach] ‣Happy Choo Choo (a) - Otto Sieben [Krabs using Gary to find more change] • ? - Michael Bolger, Nicolas Carr [SpongeBob rearranging the wall rivets] ‣Hawaiian Link (b) - Richard Myhill [Gary getting tired] • ? - Michael Bolger, Nicolas Carr ["We ain't got time for that!"] ‣Danger HQ - Norman Dane [SpongeBob looks at Gary] ‣Harp Ding - Nicolas Carr ["Oh, okay!"] • ? - Michael Bolger, Nicolas Carr [Krabs tells SpongeBob to paint the Krusty Krab] ‣Bobsled - Caesar Giovannini, Wayne Robinson [at the laundromat] • ? - Michael Bolger, Nicolas Carr [wagon full of money] •Vibe Sting - Nicolas Carr ["Hey, what's the big idea... er?"] ‣Dombummel - Gerhard Trede [arcade] ‣ ? [old guy talking to a security guard] • ? - Nicolas Carr, Sage Guyton, Jeremy Wakefield [SpongeBob finishes painting] ‣Hawaiian Sting 1 - Sage Guyton, Jeremy Wakefield ["You haven't seen a crab walking around with a snail, have you?"] ‣Dramatic Bridge 3 - Phillip Green ["Mr. Krabs, what have you done to my Gary?"] ‣Dombummel - Gerhard Trede [SpongeBob enters the arcade] ‣Befuddled Gent - Phillip Green [Krabs wearing a dress] ‣Steel Licks (b) - Jeremy Wakefield [Gary's sick] ‣Befuddled Gent - Phillip Green ["You look fine to me."] ‣Cockney Capers 1.3 - Ray Davies* [Krabs leaves the restroom] •Steel Sting - Jeremy Wakefield ["Uh, yeah..."] •Drama Sting - Sage Guyton, Jeremy Wakefield [Gary sees all of the coins] ‣ ? [buckets of change] • ? - Jeremy Wakefield [Gary not attracting any change] ‣Cloak and Dagger [#70] - Phillip Green ["Mr. Krabs, for shame!"] ‣Dramatic Bridge 1, 3, 4 and 7 - Phillip Green [Gary attracting everyone's change] ‣Monster Wave - Nicolas Carr, Fabian Fernandez, James King ["Jackpot!"] •Hawaiian Trax - Sage Guyton, Jeremy Wakefield [Krabs in the hospital]
This episode is resented by some fans due to Mr. Krabs being shown in an extremely negative light, symbols of animal abuse (Gary being used as a tool to attract money), and Krabs committing a huge account of thievery. But they were also happy that he paid the price at the end.
Mr. Krabs keeps calling Gary by a different name. Also, he mispronounces snail, instead saying that Gary is a "sneagle."
SpongeBob keeps getting impossible jobs to do at the Krusty Krab to keep him busy.
This is, by far, Mr. Krabs' third most villainous deed in the show.
This was originally going to be in Season 8, but this episode was aired in 2010 and cannot be paired with an episode that's in another season because "Gramma's Secret Recipe" is part of Season 7 along with "The Cent of Money" which means both episodes to be a part of Season 7. Season 8 was moved and aired in 2011. 
The Cent of Money is a pun on "The Scent of Money."
When the scene shows the fish playing the arcade games, one of them has a character and game similar to Pac-Man.
When Mr.Krabs calls Gary "Sneagle," it sounds very similar to a character in The Lord Of The Rings, whom is named "Smeagol."
Usually, in reality, the only coins that work in arcade machines are quarters. Also, coins cannot be obtained magnetically, because they are not made out of magnetic material (although some currencies that use coins can be attracted by a magnet such as a 1, 2 and 5 cent Euro coins). Of course, it's possible that the coins in Bikini Bottom are made of a different material than the American coins they're based on.
It was impossible for SpongeBob to see the difference of the bolts with a magnifying glass, as he said they are off by nanometers, and just 1 nanometer is 5 atoms long, so SpongeBob would need a microscope to see the difference. Although, since sea creatures are smaller than people, it may be easier for them to see smaller sizes.