Payback on energy.

DON'T just sit in traffic this summer complaining about high gasoline prices. Do something.

Fine, you may say, but what? Well, our recent experience with $40-a-barrel oil helps to spotlight a possible use for a sector mutual fund.

By no coincidence, sector funds specializing in energy stocks rang up strong gains lately as the price of oil climbed from under $27 a barrel last September to as high as $42.45 early this month.

Take a look at the Class A shares of the $574 million State Street Research Global Resources Fund, which leads the long-term performance list of all 77 funds in its category tracked by Bloomberg. Through the end of last week it had gained 37.9 percent over the past year. Over the past five years, its average return was 25.1 percent, versus a 1.3 percent average decline for the S&P 500.

Now, every experienced fund investor knows the problem with sector funds. They're poorly diversified, and thus subject to big performance disappointments.

Before its recent stretch of victories, State Street Research Global Resources trailed the S&P 500 for five of the six years from 1993 through 1999, gaining 3.9 percent a year while the S&P 500 was soaring at a 23.3 percent annual rate.

Future risks? Analyst Frederick Leuffer at Bear Steams & Co. said the other day that U.S. crude-oil prices could fall back to $20 a barrel by early next year as Saudi Arabia and other producers pump more.

So how in the world could a fund like Global Resources be used as a conservative risk management tool? By matching it up against a liability in one's family accounts--specifically, gasoline expenses for the car(s) as well as home heating costs.

With a few calculations, anybody could figure out an appropriate amount of shares in an energy sector fund to hold as a hedge against the future vagaries of world energy markets.

If the fuel bills go up in the future, so might the value of one's energy-fund investment. Conversely, if the fund went down, one would presumably have the consolation of seeing the fuel bills drop too. While there are no guarantees this will always work out perfectly, it's a reasonable expectation.

This is all theory. Before it can be put into practice, there may be several questions to answer and obstacles to overcome. A call to State Street's customer-representative hotline confirms that sales of Global Resources shares have been restricted to a limited number of brokers since April 1.

Then again, it's a load fund anyway, and there are ample alternatives available from such other companies as the Vanguard Group, Fidelity Investments, ProFund Advisors and Rydex Global Advisors.

Once an appropriate fund is selected, one needs to have a few thousand dollars or more in spare capital to commit to the plan. If you are blessed with a lot of that capital, I acknowledge, you may be just as happy bearing your energy costs without a hedge. As long as the costs aren't keeping you awake at night, why take the trouble?

Nevertheless, there may be a certain kind of mid-range investor who finds the whole fanciful idea of hedging with funds appealing. The same principle could be applied elsewhere as well--perhaps in the realm of mortgages, for instance.

What we have here is an opportunity for thinking creatively.