Brunner, John. Total Eclipse

John Brunner, Total Eclipse (1974). Mess with eugenics and capitalism-like structures merged into one institution, y'all might wind up dead.

Here's the relevant bit (big spoiler alert):

“But that’s absurd,” Lucas said after a pause. “Going bankrupt— well, it could bring down a civilisation, but it couldn’t wipe out an entire species.”
“It could!” Ian insisted. “Look, it occurred to us to wonder whether the Draconians traded among themselves, and we decided yes, they must have, but it never occurred to any of us to ask what kind of currency they employed.”
Cathy jumped to her feet. “The printed crystals!” she burst out. “Those can’t have been money!”
Karen shouted. “You’d find money all over everywhere, not concentrated in great big storehouses—”

[like, an hour later] 

“Am I being obtuse?” Karen said. “Or have you not yet explained how going bankrupt killed them off?”
“I was just coming to the details of that. I think I already said— excuse me, but my head is buzzing insanely with all the implications— I think I said I started asking what an individual could accumulate by way of reward, or payment.”
There was a brief hush. Nadine ventured, “Promises that when he became she, there would be outstanding genetic lines reserved to— uh— to her?”
“That’s it. That’s what killed them.” Igor leapt to his feet and started pacing back and forth, thumping fist into palm. “I’ve almost got it,” he said. “You mean that without realising what they were doing, they restricted their genetic pool until it became dangerous, and then it was too late. Like fortunes being concentrated in the hands of a few ultra-powerful families? A sort of genetic capitalism?”

(JLW)

Lord, Karen. Galaxy Game

Karen Lord, Galaxy Game (2015). A sequel to The Best of All Possible Worlds. Features a world, Punartam, where resources are allocated by the interplay of two formal media, called "social credit" and "financial credit." There is a kind of mapping between divisions such as market and gift economy, or between money and social capital, onto the division between basic needs and wants/luxuries -- all suitably science fictionally estranged and disheveled, of course. Here are the relevant snippets:

Haviranthiya told him very soberly that it appeared Academe Maenevastraya had registered a prior claim on his acquaintance and he could no longer provide Rafi with an Academe Surinastraya recommendation as a starting nexus for future Punartam interactions.
[...]
   "And your essentials," Ntenman continued.
   "There's nothing wrong with them. You should approve of that."
   Essentials were harder to understand, but after Lian dumped a message and a quantity of voice-access credit into his channel, things became clearer. The credit was "a loan, not a gift", and the fact that Lian had extended it made Lian one of his primary essentials. "Stay neutral," Lian's message warned. "Do not accept credit from non-Cygnians."
[...]
   "Your keys are your peers," Lian's message explained further. "I've introduced you to a couple of mine and I'll introduce you to more in time. I know your family and I shared food and drink with you in public, so I'm one of your first-tier keys. Keys you meet through me will be your second-tier keys. You will have to acquire more keys by your own efforts."
[...]
   He quickly discovered that for every variant of the credit system, there were several academic interpretations and models on how they should work. "Economic credit is mere financial engineering," sneered his Academe guide. "Social credit is art."
[...]
   "Yes, that's survival. But social credit determines what you will eat, and where, and with whom."
   "And I get my financial credit from my essentials but social credit from my keys."
   "More or less. That depends on where your nexus is located and the allegiance of your keys. Sometimes it's worthwhile to have a broad representation, but sometimes a nexus will refuse to acknowledge certain keys or networks, or will itself be shunned by other networks." Ntenman exhaled sharply, already frustrated. "It's a complex formula. The size, density and degree of overlap of your networks is measured, your net worth is calculated with reference to recommendations from your keys, and only a fully qualified Credit Assessor can work out the result."
   "But good social credit makes my financial credit more valuable, is that right?"
   "More or less. You're in a higher consumer bracket for some things."
   "So this is good! I have a nexus and I'm making a start on my social credit. I'll be able to pay you back."
   "Don't be rude," said Ntenman, only half-joking, and Rafi belatedly remembered that on Punartam, it was bad manners for anyone, be they creditor, debtor or completely uninvolved, to harp on an unpaid debt.    "So, financial credit is what gets me food and shelter?" Rafi asked. He had discovered that teaching him the basics appeared to put Ntenman in a better mood, as if doing so re-established the correct order of things.

For other exotic trust currencies, see entries for Cory Doctorow, Iain M. Banks, Michael Swanwick, and Jack Vance.

(JLW)