The Yes Men

The Yes Men are a group who use any means necessary to agree their way into the fortified compounds of commerce, and then smuggle out the stories of their undercover escapades to provide a public glimpse at the behind-the-scenes world of big business.
The stories are often both
shocking and hilarious. They have been called "the Jonathan Swift of the
Jackass generation" by author Naomi Klein. The Yes Men have
impersonated World Trade Organization, Dow Chemical Corporation, and
Bush administration spokesmen on TV and at business conferences around
the world. They do this (a) in order to demonstrate some of the
mechanisms that keep bad people and ideas in power, and (b) because it's
absurdly fun. Their main goal is to focus attention on the dangers of
economic policies that place the rights of capital before the needs of
people and the environment.
http://theyesmen.org