YouTuber standupmaths posted this video below about why he thinks Australian banknotes are some of the best in the world. And it has nothing to do with its design (some love them, some hate them) but more about how they increase in value and in size based roughly on a mathematical log scale.
He includes a comparison with British Pounds as well and notes that the UK Pound not only increases in length as the value goes up, but it also increases in width as well. Some people don't like this because it means the notes don't fit nicely in a stack, but if you consider the pure usability and accessibility of bills with these features (especially for people with disabilities), it's quite a good thing.
This past Wednesday, Australia officially rolled out a newly redesigned $5 bank note that sports even more security features while maintaining the country's elegant and colorful money scheme. Of all of the countries that I've seen money for, Australia's bills are probably my favorite. They seem to address a number of accessibility issues that other countries seem to forget and this new note is no exception -- it has features for the blind too.