Exchange-traded funds, which share the design of mutual funds but trade on exchanges like stocks, are no fad in the financial world. So far in the United States, ETFs have attracted more than $600 billion in assets. That's tiny compared with the $12 trillion invested in conventional mutual funds, but ETFs are gaining fans quickly.

Tom Lydon, president of the Newport Beach, Calif., firm Global Trends Investments, is one of a growing number of financial advisers who favor ETFs over mutual funds. Lydon, coauthor of a new book, iMoney: Profitable ETF Strategies for Every Investor, and a blogger at ETF Trends, says between 80 percent and 90 percent of his firm's clients now have pure ETF portfolios. Lydon recently spoke to U.S. News about why investors are gravitating to ETFs, where the industry is headed, and which funds to buy now. Excerpts:

Why choose an ETF over a mutual fund? We're seeing more and more investors make that choice, and the big reason is that many individual investors have lost faith and trust in the mutual-fund industry. After a big run-up in the 1990s and a big decline in 2000-02, many investors felt that the fund companies were going to take care of them. But when the S&P 500 declined 47 percent and the Nasdaq declined 75 percent, these mutual funds felt the pain as well.

During this time, investors were calling their fund companies, wanting to hear what their fund manger was doing, and some would say that they're thinking about making a move. Meanwhile, people at the funds were telling them not to time the market, to take a long-term perspective, and they were very much

DETROIT (AP) -- With another huge quarterly loss now in its rearview mirror, General Motors Corp. faces the ominous task of raising revenue by selling cars rather than trucks.

But even with plans to boost production of its hot-selling fuel-efficient models and cut output of unpopular trucks and sport utility vehicles, the company is running short on time if it keeps burning through more than $1 billion in cash every month.

GM on Friday reported a $15.5 billion second-quarter loss, the third-worst quarterly performance in its nearly 100-year history. Through the first half of the year it used up more than $7 billion in cash, including $3.6 billion from April through June.

Company officials seem optimistic that a combination of expense cuts, increased car production and the introduction of new vehicles will slow the cash burn and eventually return GM to the black. But they're still prepared for an economic downturn that could last until 2010.

"Ultimately we're going to have to grow the business in a tough market," conceded Chief Financial Officer Ray Young.

The third quarter didn't start well for the company. On Friday it reported July sales fell 26 percent compared with the same month last year as high gas prices continued to cut into pickup truck and SUV sales. U.S. sales overall fell 13 percent for the month.

The company couldn't produce enough small and midsize cars to meet demand in the first half, but that