Here's my Etch-A-Sketch simulator. All the basics were set up very quickly in a couple of hours at most and all of the rest of the time was spent trying to get the shake-to-clear-the-screen effect to work without being really laggy.
Controls:
Arrow keys to move the cursor
X to shake/clear the screen
Z (hold) to move one pixel at a time (for great justice detail)
There's also a few options on the pause menu (P/Enter) if you want to make your art look really janky.
Please share your horrifying art. :)