The world's financial markets have been embroiled in the Greek and eurozone debt issues since last summer. Markets fly higher one day based on "positive" news from Greece and collapse the next, when the "positive" news from the previous day doesn't materialize. This week's action in financial markets, more or less mirrored in commodity markets, was a classic example of this good news, bad news flopping around. Currency valuations have also been extremely volatile, with the dollar showing huge gains throughout most of the months since last August. The chart below shows the dollar index from last August when the euro mess initially hit the headlines in a major way.The price charts for corn, wheat and soybeans during this same period have al...