Hello, I'm not an artist, but I hope you'll find my idea to be interesting.
So, http://blackboard.byethost2.com is a web site I've created just for fun. It's a very simple site: black square canvas, everybody can draw on it whatever he or she wants and save. Everybody tries to fill its emptiness. But the point is that with every new drawing saved the previous drawings are darkened so the canvas is "bottomless" - finally, it "absorbs" everything, every your drawing, every your idea. So we try to fill the emptiness of the black square completely - and we can't What do you think about it?
Now everything is saved. Nothing will be wiped into the void. You can navigate through the history of the board.