AVONDALE, Ariz. -- The little blue house rests on a few pieces of wood and concrete block. The exterior walls, ravaged by dry rot, bend to the touch. At some point, someone jabbed a kitchen knife into the siding. The condemnation notice stapled to the wall says: "Unfit for human occupancy."

The story of the two-bedroom, one-bath shack on West Hopi Street, is the story of this year's financial panic, told in 576 square feet. It helps explain how a series of bad decisions can add up to the worst financial crisis since the Great...