There’s something satisfying about the thought of a message hidden in plain sight. A puzzle whose very existence is the prize to find. A maze with cheese at the end. Good cheese. None of that Kraft singles crap. Gouda.
Steganography has a history stretching back to Greek philosophers. One if its most widely used current incarnations involves the manipulation of image files.
Kodak Image 7 from the True-color Kodak test images
Gouda goes to the first commenter with the message.
A Stranger's Sojourn 