How does the dollar's free fall on world currency markets affect you? That depends on who "you" are. Below is a guide to whether a weak dollar is cause for celebration — or despair.

If You Are ...

A Wal-Mart shopper — slight despair, but not much. Many of the goods sold at Wal-Mart and other discount stores are made in China, and the Chinese currency, the yuan, is, in effect, pegged to the dollar. So the weak dollar has little effect on the price of goods sold at those stores.

If You Are ...

A worker at a Boeing plant — celebration, with one caveat. The weaker dollar means foreigners can buy more of what you make. That new Boeing 787 is now a lot cheaper for someone paying for it with euros or other currencies. The flip side is that a weak dollar makes U.S. firms vulnerable to a foreign takeover, because the firms themselves are also cheaper.

If You Are ...

A commuter driving a gas guzzler — despair. A weak dollar means higher oil prices and, therefore, higher prices at the pump. Why? Those oil-rich sheiks get paid in dollars, and the dollar doesn't go as far. So the market price adjusts to compensate — it's already near a record high of about $80 a barrel.

If You Are ...

An American tourist vacationing in Paris — despair. Your dollar buys fewer euros, so brace yourself for $7 cups of coffee and $50 taxi rides across town.

If You Are ...

An American consumer with a taste for French wine and German cars — despair. You can expect to pay more for your BMW and Beaujolais Nouveau as manufacturers raise prices to compensate for the weak dollar.

If You Are...

A German tourist in New York — celebration. Your euro buys many more dollars than it once did, so everything seems cheaper. It's as though all of America is on sale.

If You Are ...

The owner of a small factory in China that makes widgets for Americans — slight despair. The oil you need to run your business is now more expensive, thanks in part to the weak dollar. But you get paid a fixed price for your goods, more or less pegged to the dollar, so you end up eating those higher energy costs.

If You Are ...

Chairman of the U.S. Federal Reserve — slight despair. You'd like to "protect" the dollar from further weakening, and the best way to do that is by raising interest rates. But raising interest rates slows economic activity, and that's not good. No wonder Alan Greenspan retired.

— Eric Weiner