Not much Sketch hacking today, but I read an interesting Article in the new issue of c't (no link to the article this time, as it's not online), which I suspect might be an April Fool's Joke. If it is, it's a pretty good one.
A c't reader discovered some strange artefacts in an American DVD called "The March Is Over". The c't team investigated this and couldn't find anything at first, but eventually saw some flickering out the corner of the eye. Stepping frame by frame didn't produce any results but after they'd filmed the screen with a video camera they found the slogan "Don't drink and drive" on one image and they found two other such subliminal messages in two other scenes.
They surmise that the slogans are "subpictures" which are usually used for subtitles. Subpictures are normally not shown when single stepping.
Interestingly enough, these messages weren't present in a copy they created with DeCSS, although they should have been, so the question remains, just how they are embedded in the DVD data. Even though subliminal messages don't work, if this is a true story, things like this would be another good reason to be able to use DeCSS or similar tools legally.
The article goes on with some conspiracy theory that behind this is a scheme for mass manipulation and that this might be just another reason for DVD-Consortiums use of region codes.
 I had written most this entry when I realized, that this title alone is the strongest hint that it's indeed an April Fool's Joke...