The power of falling dollar

Affects export. Impossible to compete with price of products made in US.
After the last dollar-induced crisis in the mid-1990s, many companies set up operations in the U.S. and Asia so that shifts in currency values would tend to balance each other out—so-called natural hedging.
And the euro itself, introduced in 1999, eliminated currency risk for trade among the 15 nations who use it. Most European countries are still each others' largest trading partners.

The current financial crisis—perhaps the biggest since the Great Depression—has turned Federal Reserve Chairman Ben Bernanke into a reluctant revolutionary.
The two moves represented a new level of direct Fed involvement in the financial markets and made it clear that Bernanke would take any step needed to prevent a financial catastrophe.

two of the strongest currencies are in countries whose central banks have kept rates low: Japan and Switzerland.