The FBI arrested 11 suspected Russian spies for passing U.S. information to Russian spy agents using wireless networking and steganography.
Steganography is the process of writing hidden messages in such a way that no one, apart from the sender and intended recipient, knows of the existence of the message, a form of security through obscurity. The message can be hidden in pictures, text and many different forms.
For more on this story please refer to the links below:
The Economist – http://www.economist.com/node/16486569?story_id=16486569
Linux Security – http://www.linuxsecurity.com/content/view/152728/169/