Honestly, now, who passed through childhood without drawing on walls? Hope there aren't many of you who didn't do that just once. I remember killing my parents and grandparents with my precocious drawing imagination. I luckily still draw on walls but not with so bad consequences. Many others still draw on walls too, and look what they came up with.
So, looks like we found the replacement for plain white or wallpaper. And it sure is original and not found in every house. And what's more, is that it's made by you.
Found this brilliant ideas, here.