Chances are civil protests on Mars during the early settlement period will consist largely of building takeovers or sit-ins. What else could the angry youths of a bubble colony do? The Institute for Applied Autonomy, a group of anonymous tech-happy artists, already has an answer -- protest robots.
The group makes robots to stage protests where a human might be in danger or too restricted. The Institute's Graffitiwriter is remote-controlled robot like those used by the police and military, but this one can paint a sidewalk message from a color palette when conditions prohibit a decent spray job. It's essentially a rolling color printer aimed at the concrete. A larger version, called the Streetwriter, is an answer to skywriting of sorts and can be hitched to a car. Huge dark-blue letters might show up well on the Martian soil or concrete near VIP landing pods.
The anthropomorphic Pamphleteer hits passersby with protest literature and is designed with disarming George Lucas-style cuteness. Genteel voters and consumers need no longer be berated by wide-eyed idealists, over-zealous activists or self-righteous longhairs reeking of patchouli oil; it's only C-3PO's cousin reminding them of impending environmental doom and corporate greed.