The free Coral CDN (http://www.coralcdn.org/ http://www.coralcdn.org/) already does something like this. It caches the link the first time it is visited. But ra

The free Coral CDN (http://www.coralcdn.org/ http://www.coralcdn.org/) already does something like this. It caches the link the first time it is visited. But rather than redirecting you to the original page if it’s up, it always show its own mirror of the page (on its nyud.net domain).