Money in the 21st century sense was not used on 24th century Earth. The exact nature of the Federation economy is difficult to describe; while money had not entirely ceased to exist, it did not play the central role in the lives of Federation and Earth citizens that it once did. The descriptions given by various Federation citizens are as follows:
* Kirk told Spock about 20th century Earth: "They're still using money. We need to get some." Later on, while Kirk was having dinner with Gillian Taylor and was unable to pay in the restaurant, Gillian asked sarcastically, "Don't tell me they don't use money in the 23rd century," and Kirk told her "Well, we don't." (Star Trek IV: The Voyage Home)
* Leonard McCoy responded to Chang's constant quotations of William Shakespeare during the battle of Khitomer that "I'd give real money if he'd shut up." (Star Trek VI: The Undiscovered Country)
* Picard tries to explain to Ralph Offenhouse from the 20th century that there would be no need for his law firm any longer: "A lot has changed in three hundred years. People are no longer obsessed with the accumulation of 'things'. We have eliminated hunger, want, the need for possessions." (TNG: "The Neutral Zone")
A Ferengi coin
* When Lily Sloane asked how much the USS Enterprise-E cost to build, Picard tells her "The economics of the future is somewhat different. You see, money doesn't exist in the 24th century... The acquisition of wealth is no longer the driving force in our lives. We work to better ourselves and the rest of Humanity." (Star Trek: First Contact)
* When Nog suggests that Jake should bid for a baseball card in an auction, Jake says "I'm Human, I don't have any money." Nog replies "It's not my fault that your species decided to abandon currency-based economics in favor of some philosophy of self-enhancement." Jake says "Hey, watch it. There's nothing wrong with our philosophy. We work to better ourselves and the rest of humanity." Nog then replies "What does that mean?" Jake responds "It means we don't need money!" Nog quickly points out, however, that Jake wouldn't be able to bid or borrow. (DS9: "In the Cards")
* Jake: (big smile) "I sold my first book today." Quark: "Really? How much did you get for it?" Jake: "It's just a figure of speech. The Federation News Service is going to publish a book of my stories about life on the station under Dominion rule. But they're not paying me." (DS9: "You Are Cordially Invited")
* Tom Paris says about the significance of Fort Knox: "When the New World Economy took shape in the late 22nd century and money went the way of the dinosaur, Fort Knox was turned into a museum." (VOY: "Dark Frontier")
"When fascism comes to America, it will be wrapped in the flag and carrying a cross." - Sinclair Lewis
"Those Who Would Sacrifice Liberty for Security Deserve Neither." -Benjamin Franklin