A modest proposal of Larry Niven, from the time of the last US deflationary era. Niven proposes to mint cash by "the Roentgen Standard": coins of plutonium. The metal itself is expensive, rare, and much better controlled than gold. So forgery is less of a problem than with the gold standard.
Market spending immediately goes up: you cannot hold on to cash for long (it "[literally] burns a hole in your pocket"). Progressive taxation occurs automatically, because the rich need to get rid of their excess cash, and the other rich just won't accept more money. Oh, and saving doesn't work too well either, because money has a half-life.
Banks don't jeopardize the scheme, either: You want to store HOW MUCH PLUTONIUM in one place? There's a physical limit to storing more than a certain critical mass of plutonium!
Thieves get caught red-handed (except maybe it's blue).
The problem of nuclear waste is solved: today it's the substance nobody wants, but in the Plutonium Economy it's a substance that lots of people (those who haven't enough money) want. 1980s-style defense spending (i.e. perfecting MAD) goes out, as building warheads is literally throwing away good money.
It all just clicks together! A pity Niven never wrote the short.
See negative interest money for some serious Economics that's immediately (and literally) relevant.