Here is another Raspberry Pi project worth trying. Etch-A-Snap is a Pi powered Etch-A-Sketch camera that snaps photos like any other camera but outputs them by drawing to a Pocket Etch-A-Sketch screen. Photos are processed down to 240×144 pixel 1-bit drawings with Pillow & OpenCV before getting translated into plotter commands.
The Etch-A-Sketch wheels are driven by 5V stepper motors mounted into the 3D printed frame. This is completely portable and powered by batteries.