Google's authentication-less on-the-fly image resizing service
I found it while poking around the Google+ HTML. Jotting down some notes felt like a good idea, so here goes. If you know more about this API, let me know, please!
(Word of warning: I spent ~30 minutes on both my experimentation and this here write-up, so it might not be the most thought-provoking, brilliant thing you read today.)