Over the years, there have been several attempts in the US to popularize the gold dollar coin. Since 2000, for instance, there have been gold coins with Sacagawea on them. When these first came out, I remember it being a big deal when vending machines were updated to accept the coin. The excitement surrounding the new coins has definitely warn off, however, and the only time I really run into them now is when I've bought stamps from the machines at post offices and got the gold dollars as change.
Based upon what I've read, it appears as though the only way dollar coins will really catch on is if the government phases out the dollar bill. Change isn't always easy (pun intended), but countries like Canada and the UK have proven that people will get used to the new currency rather quickly. So there you have it ladies and gentlemen, one way of reducing our deficit would be to simply do away with the dollar bill.