This is amazing. Aparently there's a move for a South America wide silver currency.
Latin American Congressmen Consider The Silver Coin
If you want to know what this means. And what the arguments are about fixed, commodity backed currencies, there's plenty on the alt.money tribe.
Executive summary : fixed, commodity backed money avoids some of the problems of fractional reserve banking. (We're not in a crazy dash for growth because of hypercompetition to pay back the money that was borrowed into existence)
But I'm starting to suspect that it's the ideal money for feudal aristocrats. (And wannabe aristocrats)