The Yes Men Strike Again
McDonald's Interactive

The Yes Men are a group of activists who put on fake presentations at real conferences in order to get their messages across (that is a horribly boiled-down explanation). Apparently they showed up at the Serious Games Summit and put on a pretty funny PowerPoint presentation about McD's.

More info here.

These are the same guys (The Barbie Liberation Organization) who swapped voice chips from Barbie dolls and GI Joe figures and put them back on store shelves.

The Yes Men - Up Came Oil

The ENTIRE Yes Men movie on Google Video.