One of the most alluring dreams in science fiction is the post-scarcity society — a place or time where nobody goes without, because technology has improved. But when you dig deeper, most post-scarcity worlds still have some scarcity, because otherwise it's hard to tell a story about them. See for yourself!
The Jump 225 trilogy by David Edelman: The world of these books is, in many ways, post-scarcity. Human existence has been transformed by body-enhancing tech called bio/logics. However, access to particular much-desired technologies is by no means guaranteed, and some people have better implants than others. And the scarcest commodity of all is access to Multireal (a tech that can parse through possible futures and pick the ideal one) which people fight over throughout the books.
Star Trek is the classic example of a post-scarcity society that still has scarcity. Last year, there was a huge essay in Medium (and a response in Slate) about scarcity in Star Trek. But suffice to say, the Federation has no money and no real want — except that there are always famines and epidemics where the cure has to be transported across the quadrant. And if you want a home-cooked meal at Joseph Sisko's restaurant, that's a scarce item. And in the Original Series, there's a constant shortage of Dilithium crystals.
Down and Out in the Magic Kingdom by Cory Doctorow features a world that has conquered hunger and other kinds of want — nobody need go without. Except that there's a reputation currency, called "whuffie," that becomes the new resource that everybody strives for. And if you don't have any "whuffie," then your life isn't all that much fun.
The Diamond Age by Neal Stephenson: In this book, fabricator technology can generate anything that people have the designs for. That said, the poor still receive smaller allotments of energy and resources so their fabrication requests take longer to come through. Also, they do not have access to large-scale fabricators. The feeds that pass goods from central fabricators to customers are owned by 'phyles' (cultural agglomerations eg. the Han, New Atlantis, Nippon) that are competing for a share of the Chinese market. So while a lot of goods and services are provided for free, there is still relative scarcity thanks to economic competition.
The Uglies series by Scott Westerfeld includes the use of "reputation economies" (a bit like Doctorow's "whuffie"). In the third book (Extras), a Japanese urban agglomeration institutes merit-based systems for citizens who complete tasks that help their community while a "face rank" system tracks popularity. People check their face rank obsessively.
Charles Stross' Singularity Sky and Iron Sunrise Here, FTL communications are enabled by 'causal channels' that are, in turn, driven by entangled quantum particles that are both expendable and need to be transported at slower-than-light speeds. This makes them both scarce and expensive.
The TCity trilogy by Mark Adlard. In these books (Interface, Volteface and Multiface) there's an automated city in which the citizenry has no need to work and exist as one big mass of consumers. But discord is fomenting and the leaders discover that the scarce resource that all the citizens are hankering for is work.
And in fact, a common trope in a lot of these books is the scarcity of immaterial and intellectual pleasures in a post-scarcity society. In Stross' books, creativity and intelligence are also valuable (and scarce) resources, especially in Accelerando. Another possible example: in Iain M. Banks' Culture novels, it's an ineffable uniqueness associated with particular goods/services that's scarce — e.g., good seats to a concert, despite the fact that anyone anywhere could enjoy a simulated experience of the concert, that's (objectively speaking) no different from being there.
Damon Knight's A is for Anything: In this classic, a matter replicator called the Gismo is discovered and it makes material items free and unlimited. The side effect, however, is that the only valuable commodity becomes human labor. This ultimately gives rise to a slave economy.
The Collapsium (Queendom of Sol series) by Wil McCarthy: This book includes a future in which humanity has attained near-immortal status and limitless energy due to the harnessing of programmable matter and a material (made out of black holes) called collapsium. The latter can transport materials across huge distances almost instantaneously. But collapsium itself, presumably, remains a scarce resource, given that it can only be harnessed from black holes. And the print plates of the replicators are valuable and scarce resources, because they're among the few things that can't be copied/'printed' by another replicator.
The Quantum Thief by Hannu Rajaniemi takes place in a far-future, posthuman society, in which people can easily program their bodies and environments. The scarce resource/unit of currency in one particular culture (the Oubliette) is time left to live.
Troy Rising by John Ringo: The Glatun, an alien race encountered by humanity, use 'fabbers' that can produce everything they need. The only scarce resource in their society is the helium required to run the fabbers.
The Long Earth by Terry Pratchett and Stephen Baxter: A device called the stepper enables humans to step into parallel worlds, thus ending scarcity of resources. However, it turns out that device only taps into an innate 'stepping' ability that exists in most people but not in others. So, for some (dubbed 'phobics'), the stepping ability itself is the scarce resource.
Zardoz: The Eternals who live inside the Vortexes enjoy a post-scarcity society that, nevertheless, suffers from a shortage of sex, violence, and associated heated passions. As a result, they're also lacking children, and the concept of death.
George O Smith's Venus Equilateral series: The invention of a matter replicator (thus implying a post-scarcity era) causes so much economic upheaval that a new element had to be invented that explodes under the replicator's beam. This non-replicable element then gets used as a medium of exchange.