Frozen fuel.

Japan, a country almost totally dependent on foreign fuel, has embarked on a long-range program to determine the economic and environmental feasibility of extracting frozen methane hydrate that's located off its central Pacific coast. Methane hydrate--methane gas surrounded by a lattice of ice molecules--burns when exposed to flame, but any change in temperature or pressure causes the compound to gasify. Next year alone, Japan will funnel US$120 million into research that may someday lead to viable recovery methods for the volatile fuel.

Conservative estimates place the total global amount of methane hydrate supplies at twice that of known fossil fuels. Although methane is a known greenhouse gas, it is unclear how exploiting it in this form--which amounts to 3,000 times the volume of methane existing in the atmosphere--could impact climate change.