Harry Potter
The practical utility of Harry Potter is, admittedly, somewhat limited. One cannot exchange a first edition for groceries at Tesco (though one could sell it at auction and then purchase groceries). The spells detailed in the books do not actually function when attempted. The life lessons, while valuable, require significant interpretation before practical application.
However, Harry Potter does serve several practical purposes. It has motivated millions of children to develop reading skills, a utility that compounds over a lifetime. The franchise has created tens of thousands of jobs across publishing, entertainment, retail, and tourism sectors. The Wizarding World of Harry Potter theme park attractions generate billions in economic activity.
For educators, Harry Potter provides a pedagogical tool of remarkable versatility. The series can illustrate concepts from ethics to chemistry (potion-making maps surprisingly well to actual laboratory procedure). The books have become a gateway to more complex literature for reluctant readers.
Money
Money's practical utility is so comprehensive that attempting to enumerate it seems almost absurd. Every economic transaction in modern society relies on money. Food, shelter, healthcare, education, transportation, communication - virtually every human need in contemporary society requires monetary exchange. Money is not merely useful; it is infrastructurally essential.
The practical innovations money has enabled are staggering. Interest rates allow for the transfer of value across time. Insurance permits the distribution of risk across populations. Investment enables collective funding of enterprises no individual could afford. These financial instruments, whatever their flaws, have facilitated unprecedented human coordination.
Modern money has achieved something remarkable: the ability to store value across time and transfer it across space with minimal friction. One can earn money in London on Monday, transfer it to Tokyo on Tuesday, and spend it in Sydney on Wednesday. This practical capability would appear genuinely magical to anyone from previous centuries.