What is Visual Cryptography Visual Cryptography is a special encryption technique to hide information in images in such a way that it can be decrypted by the human vision if the correct key image is used. The technique was proposed by Naor and Shamir in 1994. Visual Cryptography uses two transparent images.
Focusing on the consequences of the Patriot Act and how the US government upped the security on civilians after 9/11, this is a really nice graphic that gives a scary visual on the expanded powers of the national government in the name of security. It's from the ACLU, so this gives a pretty good perspective of, specifically, curbed liberties.