This is a simple web application that is able to extract images from urls and caches them. It's using Reddit's scrapper code, with a couple small tweaks, mostly to allow it to run on Google App Engine.

The app provides a single call: /?url=, which will return a URL corresponding to the location of that image. Your app should cache that url. Please note that the URL returned may also be a redirect url, which should 'soon' redirect to the actual image when it's been extracted.