Last October, Iceland's economy tanked. Its bailout? A two-mile geothermal well drilled into a volcano that could generate an endless supply of clean energy. Or, as Icelanders will calmly explain, it could all blow up in their faces. It's spring in Iceland, and three feet of snow covers the ground. The sky is gray and the temperature hovers just below freezing, yet Gudmundur Omar Fridleifsson is wearing only a windbreaker. Icelanders say they can spot the tourists because they wear too many clothes, but Fridleifsson seems particularly impervious. He's out here every few days to check on the Tyr geothermal...