The Europeans have found a good use for those otherwise useless "404 Not Found" error pages on websites—they've become a home to ads for missing children. "Across the European Union, thousands of children go missing every year," says the homepage of the initiative, which is a collaboration between Missing Children Europe and Child Focus. "Thanks to the NotFound project, you can make a difference. Install our application and a picture of a missing child automatically gets published on every 'page not found' of your website. Together, we can find them." Brussels ad agency Famous came up with the idea. Via TNW.