Having seen the run up in food prices (not to mention the tortilla riots in Mexico) following the American government's moves to boost corn for fuel at the expense of food, the Europeans are suddenly having second thoughts.

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This means that the extra expense of fuel is more than canceled out by low capital costs.

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Fuel is the biggest single expense for airlines, accounting for about 30% of operating costs.

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The lightweight material is said to cut fuel costs, a major expense for airlines.

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It also is true for fleet-based companies as fuel is typically their second largest expense after payroll and benefits.

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Boeing says the aircraft is 20% more fuel-efficient than similar sized airliners, a selling point for airlines for whom fuel costs are their biggest operational expense.

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Fuel is the airline's biggest expense.

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Depending on the price of gas, it can take quite a while for fuel savings to make up for the extra expense of buying a hybrid as opposed to a standard, gasoline-powered equivalent.

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As the recovery slows, a growing number of people worry about a descent into competitive depreciation, as countries try to grab a bigger share of global demand at others' expense, a trend that could fuel protectionism.

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Contrary to the obvious assumption, rising fuel prices might actually cause the use of ships for freight, as manufacturers reduce fuel use not by shipping things shorter distances, but by relying more heavily on efficient sea freight at the expense of less efficient land- and air-based modes of transport.

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