Want to get rich? I mean stinking, filthy rich? The age-old secret was to strike oil, you know -- black gold, Texas tea.

But that dirty, gooey, planet-polluting, ozone-depleting stuff is just so 20th Century, so pre-global warming. What I'm talking about is tapping a gusher of a virtual green oil well.

These days, striking real oil seems to be as difficult as it is expensive, with almost 75% of land currently leased for oil exploration in the U.S. outside of Alaska going untapped. And there are only six companies who control the vast majority of those idle leases.

So if striking actual oil is difficult even for Big Oil, there is little chance that J. Paul Getty's (once the world's richest man, and founder of Getty Oil, which was later bought by Texaco) advice for success can be followed literally today: "Rise early, work hard and strike oil."

Ah, but that does not mean Getty's suggestion can't be followed figuratively.

If you want to get Getty rich today, then your wildcatting instincts should lead you to one place and one place only -- a place that is in fact the opposite of oil:

Green energy, renewable energy, eco-friendly energy -- call it hat you will. But whatever you call it, the fact is ... green is the new green.

As we all know, money follows demand. And these days, days of $4 a gallon gas, there is no greater demand than for affordable, renewable, energy. The companies, country, or person who figures out how to bring affordable, renewable, clean energy to the masses will become rich in ways that will make Getty's wealth pale in comparison.

The head of the UN section on the environment calls this "the green gold rush."

It should be no surprise that General Motors ( GM), maker of huge gas-guzzling trucks, is in free-fall while Toyota ( TM), maker of the hybrid, 45 mpg Prius, is flying high.

Green is the new green.

What form this new energy source will take is anyone's guess. Solar power is of course a hot topic (excuse the pun.) Wind energy and geothermal may be it, and don't discount the nuclear option. My pet theory (based on nothing but personal observation) is that marine power -- harnessing the energy of waves -- seems to be a no-brainer.

But whatever it is, the facts on the ground today are not that much different than when Getty struck oil. New market conditions and increased demand are making the need more acute for a plentiful energy source. Someone is going to figure it out and he who does, wins.

Let's only hope that this time we get a healthier energy source and one that we don't end up having to buy from people who are not always our friends.

Steven D. Strauss is a lawyer, author and USA TODAY columnist. His latest book is the Small Business Bible. He has spoken around the world about entrepreneurship, including at the United Nations, and has been seen on CNN, CNBC, MSNBC, The O?Reilly Factor, and many other television and radio shows. He maintains a Website at www.MrAllBiz.com.

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