More goodness for the quadcopter.
http://www.robot.tc/2010/11/vision-robot-ros.html
"Vision Robot ROS
Just a quick note that the brown-ros-pkg now includes ardrone_brown. A driver for the AR.Drone. What does this mean? Well it means, as with every new robotic advancement that skynet is one step closer to taking over, this little step gives autonomous quadrocopter robots the ability to track visually. As you'll see in this video below showing the system in action tracking an AR Marker:"