I got a fever, and the only prescription is more drawbots. Georgia Tech student Aaron Fan sent in his great delta robot that can make line drawings and shade in cool patterns.
Pythagoras is a drawing delta robot. The goals for this robot was high speed and high precision pen work. OpenCV is used to vectorize images to send to the robot for sketching.
Current progress is on version 2.5. Drawing is successful and has high accuracy. The image processing program can tell the robot to either outline an image or shade it in.
Potential further development includes using brushes instead of pens, a pen switcher for multiple colors, halftoning, and SVG support. More ambitious ideas include adding omniwheels on the legs so the bot can traverse large drawing areas.
Source files on Github.