Finance
The field of economics probably bores the average lit reader and probably most sci-fi readers as well. Yet the best sci-fi reads are the ones that construct plausible alternative financial constructs and economic environments. Whether we like it or not, our lives are immersed and enslaved to whatever the current economic paradigm is in place. So much so that most people don’t even know that alternatives exist. They don’t comprehend that the economic system that they are bound to be only an invention, and that other (maybe better, possibly worse) systems can exist.
The whole point of science fiction is to question our own current political, economic, social and scientific situation. Economics can influence how power is distributed, how society becomes structured, and how technology develops. Science fiction seeks to introduce readers to new ideas, and the subject of economics is by far the most effective in terms of changing society for the better, or worse. It can be the root of all evil, and the driver of all that can be good.
Objectivism, Atlas Shrugged by Ayn Rand.
Anti-property anarcho-syndicalism, The Dispossessed by Ursula K. LeGuin
Ration stamps, enforced consumption, Midas World, Frederik Pohl
Wooden coins, The Dragonriders of Pern series by Anne McCaffrey
Sentient High-Frequency Trading algorithms, Accelerando by Charles Stross
Criminal economy, When Gravity Fails by George Alec Effinger
Overpopulation, Stand on Zanzibar by John Brunner
Psychohistory, Asimov’s Foundation series.
The exchange of capital mediated by obs (obligations), The Great Explosion, by Eric Frank Russell