This is probably my favorite example of informational design that I have found. While looking through the mail, I found that my boyfriend had received his new Regence Insurance card. The card was placed in perforated plastic and there was 2 physical cards that could be punched out. Since he only has one person insured on his policy, they made sure that he knew the other card was blank on purpose... Awesome. I got such a kick out of dumb America, I had to share.
....and ironically, it is no longer blank.