This article from Fortune's 2006 Investor Guide is a must-read. Essentially, its about the concept of "Peak Oil," something that a lot of extremely credible people are gravely concerned about.

Here's the top-line:

"Peak oil" theorists posit that global production is at or near its historic ceiling and will begin a long, inexorable decline. They worry that America is not ready for the downturn, for skyrocketing prices and even shortages.

Some of the blogs referred to in the article are worth a read, even if you don't really buy into their alarmist viewpoint completely. I find that lifeaftertheoilcrash.net does an excellent job substantiating its points.

The following excerpt is tremendously alarming, as it refutes the idea that when the oil runs out, we can just turn to alternative sources of energy that (hopefully) are sufficiently developed.

Some specific examples may help illustrate the degree to which our technological base is dependent on fossil fuels:

1. The construction of an average car consumes the energy
equivalent of approximately 27-54 barrels, which equates
to 1,100-2,200 gallons, of oil. Ultimately, the
construction of a car will consume an amount of fossil
fuels equivalent to twice the car’s final weight.

2. The production of one gram of microchips consumes 630
grams of fossil fuels. According to the American Chemical
Society, the construction of single 32 megabyte DRAM
chip requires 3.5 pounds of fossil fuels in addition to 70.5
pounds of water.

3. The construction of the average desktop computer
consumes ten times its weight in fossil fuels.

4. The Environmental Literacy Council tells us that due to
the "purity and sophistication of materials (needed for) a
microchip, . . . the energy used in producing nine or ten
computers is enough to produce an automobile."

When considering the role of oil in the production of modern technology, remember that most alternative systems of energy — including solar panels/solar-nanotechnology, windmills, hydrogen fuel cells, biodiesel production facilities, nuclear power plants, etc. — rely on sophisticated technology.

In fact, all electrical devices make use of silver, copper, and/or platinum, each of which is discovered, extracted, transported, and fashioned using oil-powered machinery. For instance, in his book, The Lean Years: Politics of Scarcity, author Richard J. Barnet writes:

To produce a ton of copper requires 112 million BTU's or the
equivalent of 17.8 barrels of oil. The energy cost component
of aluminum is twenty times higher.

Nuclear energy requires uranium, which is also discovered, extracted, and transported using oil-powered machinery.

Most of the feedstock (soybeans, corn) for biofuels such as biodiesel and ethanol are grown using the high-tech, oil-powered industrial methods of agriculture described above.