Yet another of those things that websites make that are useful on blogs and thereby increase the number of links to their website. Not that most people do any more than put up the image thing.
Saw this on Pharyngula, who was outraged to discover he was rated G.
Not sure how he managed to get that - I'm rated PG because I've previously said the word "dead".
Oops, done it again. I'll be X-rated before you know it...