Graphic design in the service of opposition, protest or giving a voice to those that don't have one has always been an interest of mine. I've got tonnes of stuff from politically charged individuals who use their talents to disrupt, upset and challenge the status quo. I'll be digging them out over the next few months.
The Regime Change Begins at Home playing cards were a lovely response to the US-led coalitions Most Wanted playing cards - http://en.wikipedia.org/wiki/Most-wanted_Iraqi_playing_cards. The cards were designed by Noel Douglas, check out his site for more "Graphic Agitation" - http://www.noeldouglas.net/
You can still get them here: http://www.thenewpress.com/index.php?option=com_title&task=view_title&metaproductid=1511