Chris Kahn

The price of oil plunged to its lowest level in nearly six months Friday, falling below $100 per barrel for the first time since February. A drop in gasoline prices can't be far behind.

Exxon Mobil is no longer the world's biggest publicly traded producer of oil. For the first time, that distinction belongs to a 13-year-old Chinese firm called PetroChina. The Beijing company was created by the Chinese government to secure more oil for that nation's booming economy.

Oil prices are approaching last year's highs as tensions increase over Iran's nuclear program. The rise pushed gasoline prices on Friday to a national average of $3.65 per gallon, the highest ever for this time of year. Alaska's North Slope crude was up $2 to $127.99.

For the first time, the top export of the United States, the world's biggest gas guzzler, is -- wait for it -- fuel.