I’m sure this is not the first time someone has thought of using an Etch A Sketch as a photo frame, but as a digital photo frame? Might be uncharted territory. What really clinches this concept is using an e-paper display screen (like a Kindle Paperwhite), for a black-and-white display that has no back light, making it look like a real Etch A Sketch toy.
This would sit on your desk and cycle through your personal photos, however I would use it for Calvin and Hobbes and Far Side comics. I suppose a clock and calendar could also be embedded in the display somewhere.
Each image would appear to be “sketched” when coming into view. I would also include an app to allow sketching with the knobs, if you feel like doodling stuff. You could also save sketches and see them in a slideshow too.