Every day D Laferriere makes sandwiches for his children's lunches, and then draws on the bag with Sharpie markers. The drawings are AMAZING (you should check them out), but what really blew me away is that he actually has the time to draw these.
In my house, if I actually manage to get everyone's lunches and breakfasts, and everything, I consider myself somewhat superhuman.
But what a fantastic idea! My favorites so far are the bar code, the grumpy groundhog, and the stone Pi.