Heads up for endangered "404 Not Found" pages
One of our projects, called "Math 404" (math-404), soon to celebrate its sixth anniversary. The mission statement of the project is to collect and share cool, math-aware "404 Not Found" pages worldwide. However, we have noticed that it is facing a serious exsitential issue rooted in the nature of such pages. That is, every web site changes and disappears over time. The "404 Not Found" page is not an exception. The usual contents of the lost sites can survive thanks to scraping efforts such as the Internet Archive. However, the Wayback Machine legitimately dismisses "404 Not Found" pages since they indicate, by design, that the URLs accessed do not exist. In math-404 we assemble a list of dummy non-existent URLs to existing web sites equipped with a fascinating deviation from conventional HTTP 404 error. But the links cannot be permanent due to the reason described above. Until today, we have had no means to preserve the creativity and sense of humor in lost "404 Not Found" pages. We believe they deserve better.