I spent 3 months in Australia (Melbourne to be exact) around 5 years ago. They had 5, 10, 20 and 50 cent coins and $1 and $2 coins. All were easily distinguishable by size (increasing with the denomination) and were a silvery color. The $1 and $2 coins were a dull gold color, noticeably thicker than the cent coins and were distinguishable from each other by size, the $1 being larger than the $2, curiously. The bills ($5, $10, $20, $50) were also distinguishable by size (increasing with the denomination) and color. My overall experience was quite positive. I found it much easier to use than our American coins and bills. If you are wondering what they did about pennies, they rounded prices down or up to the nearest 5 cents (but only for cash purchases).

Crow's Nest: ...if the Federal government can ... it should.

No, it shouldn't! That's how the federal government grew to today's massive size. Our Constitution created limits to the federal government and we have abandoned them to our detriment.

I have long wondered why we continue to put up with the government (the ones we elect!) using the tax code to incentivize/deincentivize all sorts of things, when the single purpose of the taxes is to raise the necessary funds to accomplish the things we require our government to do (via our constitution and laws). It would be much easier to prevent our elected officials from spending our money on so many questionable things if they had to ask for funds for those things directly rather than hiding them in the tax code.