An academic at Carnegie Mellon University has set up an online gallery showing the different methods and media that have been used to publish the controversial Content Scrambling System (CSS) which unscrambles code used for decoding the DVD format.

Such systems first came to light last year when Judge Lewis Kaplan issued a ruling preventing the distribution of code for reading encrypted DVDs, namely DeCSS. The ruling was based on a section of the similarly controversial Digital Millennium Copyright Act (DMCA).

Although Hollywood won the case, preventing the publishing of code for DVD decoding, the ruling sparked off an outraged response from the internet community which came up with a number of ways to exploit loopholes and publish the code.

One of the most ingenious methods includes Copyleft.com's sweatshirts with the code printed on the front accompanied by the phrase: "I am a circumvention device".

The online gallery's curator, Dr David Touretzky, of the computer science department at Carnegie Mellon, asked: "Would merely wearing such a shirt in public constitute 'trafficking in a circumvention device' as defined in section 1201 of the DMCA?

"If code that can be directly compiled and executed may be suppressed under the DMCA, as Judge Kaplan asserts in his preliminary ruling, but a textual description of the same algorithm may not be suppressed, then where exactly should the line be drawn?"

He claimed that the gallery was created to explore this issue and point out the absurdity of Judge Kaplan's position that source code can be legally differentiated from other forms of written expression.

Other methods of 'trafficking' the code include a haiku poem explaining the code; a dramatic reading; a reading set to music; and a Yahoo greeting card.

The gallery can be found here.