Numerous consumer social movements have utilized the practice of culture jamming to undermine mainstream cultural institutions — including that of corporate advertising.

The imitation of advertisements and modification of logos are popular tactics used by jammers to disrupt the intended message of marketers. In light of this, culture jamming is sometimes mistaken for vandalism.

The term ‘culture jamming’ was first coined in 1984 by San Francisco-based collage band Negativland.

http://en.wikipedia.org/wiki/Culture_jamming