One of the divisions of the organization I work for decided to build their own prototype for their section of the Web site. They sent it to us (the Web team) and said this was what they wanted us to build them. We had already prototyped their section for them, staying of course, within our own Web site and branding standards. However they apparently felt that their level of "specialness" extended beyond our brand and therefore required a new, bastardization of our brand. What they sent us I can only refer to as, a "brandtastrophe."
Brandtastrophe: The bastardization of an organization's existing, established brand to suit the needs and preferences of a subgroup of an organization.
We've all seen this a thousand times, from the department that creates its own letterhead by smashing the organization's logo into a piece of Microsoft Word Wordart to the division that works with an outside contractor to develop a piece of collateral that has the organization's logo, but bears little resemblance to anything else from the organization. Perhaps it also has some myopic messages that were put together by the division's director during a brainstorming meeting but that no one else outside the division has ever even seen.
Brandtasrophes suck the life out of a brand and muddle the public's perceptions of it. At their worst, they effectively vandalize the organization.