Architect Ricardo Bofill transformed an abandoned cement factory in Sant Just Desvern, Spain into his personal home and offices. From ricardobofill.com:

In 1973 Ricardo Bofill found a disused cement factory, an industrial complex from the turn of the century consisting of over 30 silos, subterranean galleries and huge machine rooms, and he decided to transform it into the head office of Taller de Arquitectura. Remodelling work lasted two years. The factory, abandoned and partially in ruins, was a compendium of surrealist elements: stairs that climbed up to nowhere, mighty reinforced concrete structures that sustained nothing, pieces of iron hanging in the air, huge empty spaces filled nonetheless with magic.

The transformation process began with the demolition of part of the old structure to leave hitherto concealed forms visible, as if the concrete had been sculpted. Once the spaces had been defined, cleaned of cement and encompassed by new greenery, the process began of adaptation to the new programme. Eight silos remained, which became offices, a models laboratory, archives, a library, a projections room and a gigantic space known as “The Cathedral”, used for exhibitions, concerts and a whole range of cultural functions linked to the professional activities of the architect. The complex stands in the midst of gardens with eucalyptus, palms, olive trees and cypresses. This project is evidence of the fact that an imaginative architect may adapt any space to a new function, no matter how different it may be from the original one.

See more at ricardobofill.com