At Disney's Haunted Mansion, there's a gallery called the Stretching Room, in which you see normal portraits that slowly reveal the "secret" things going on below the customary head and shoulders frame. If you're not familiar with the attraction, you can read about it here.
Abraham Lopez (DeviantART member ArtistAbe) took the concept of the stretching portraits and recreated them with characters from the Batman universe, complete with "secrets" in the lower two-thirds. Link -via Laughing Squid