How about at a random interval once every couple months it will ask you to draw a picture of a cat in the browser and if it finds your drawing process too similar or the image too similar to one that's already in the database it will flag it without telling you. Three strikes and your out kinda rule. It's like drug tests but for the internet. Even if you did, like, a line across the screen to save time there's no way in hell it'd be the same as anything else in that database unless you are extremely unlucky.