I just saw the Yes Men movie on german television. If you don’t know what they are doing and have done so far, get informed:

The Yes Men are a group of culture jamming activists who practice what they call “identity correction” by pretending to be powerful people and spokespersons for prominent organizations. They create and maintain fake websites similar to ones they want to spoof, and then they accept invitations received on their websites to appear at conferences, symposia, and TV shows. Their newfound, self-proclaimed authority to express the idea that corporations and governmental organizations often act in dehumanizing ways toward the public has met both positively and negatively with political overtones.

[on Wikipedia]

Here’s a sneak review of their Manager Leisure Suit scam in Tampere, Finland:

You like that? Go and get the full movie, it’s a road movie documentation, it’s entertaining and compelling at the same time.