YouTomb is a research project designed by the MIT Free Culture group to track video take downs on YouTube. To succeed, the team needed to track every single video on YouTube… which is close to impossible. Instead, they built several “explorer” scripts to track what videos were interesting. One explorer tracks all of YouTube’s lists: recommended, featured, most active, and more. Another explorer picks up every video submitted to YouTube, and a third crawls Technorati.
The explorers just find the videos; a separate group of scanner scripts checks the current status of videos. It checks both the new videos and ones that have been killed to see if they return. YouTomb archives every video it finds. They display the thumbnail of the video under fair use, but they’re still determining whether they can display each video in full.