I had never heard of this before today:
A spite house is a building constructed or modified to irritate neighbours or other parties with land stakes. Spite houses often serve as obstructions, blocking out light or access to neighboring buildings, or as flamboyant symbols of defiance. Because long-term occupation is at best a secondary consideration, spite houses frequently sport strange and impractical structures.
Spite houses are much rarer than spite fences. This is partially attributable to the fact that modern building codes often prevent the construction of houses likely to impinge on neighbours’ views or privacy.
(via Boing Boing)