Read somewhere that $1 notes account for almost 50% of paper money in the US. To me it also makes sense to get rid of them (replace them with $1 coins).
The Japanese solution works very very well. the 100 yen coin (their system's $1 equivalent) is smaller than a US quarter and much lighter than a british pound coin. The 500 yen coin is about as big as a Susan B. Dollar coin, yet is still quite light. I often have as much as 2000 yen in coins in my pocket at a time, and it doesn't feel particularly heavy. Paying a transaction under 1000 yen is generally quick and pleasant.
Contrast with US $1 dollar bills, that are for some reason almost always falling apart, crumpled rags, and with the Quarter being the largest coin in common circulation, paying for something under $10 inevitably means fishing out a mix of disintegrating bills and small change.
My friend had a 500 yen coin bank, which when full held over 50,000. It was not a large coin bank.
Of course there are two other factors that don't help:
a) Previous dollar coin designs have been ugly and filled with misguided feminism (I still don't know and don't care who Susan B Anthony was, and I only know Sacagawea from The Simpsons), and
b) Previous dollar coin designs have been damn near indistinguishable from quarters by feel. Make 'em bigger or thicker or give 'em flattened edges or a hole in the middle or something! Preferably all of the above so you can look at it and say "Wow, that sure looks like a dollar's worth!"
I remembered the dollar coin as George Washington, silvery, larger than all others. And quite uncommon, especially compared to the dollar bill. Still really not something you'd confuse with quarters. Has it changed that much?
And what are those feminism attempts you seem to refer to?