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