Blogshares
Whoops... forgot to mention the Blogshares button.
It's a game designed like the stock market where blogs are sort of like companies, I guess, that people can buy and sell shares in. I have no ghastly idea how or why someone would want to play it, but I saw that it had cached an entry for my blog while I was searching Google to see if it'd spidered my new site.
I figured I oughta sign up and see exactly what it was. I'll give you a little warning, though... I'd gone there once and it had really creepy ads. Nothing worse than what you'd see on TV, but still. (Although I haven't seen any lately.) So I signed up and decided to "claim" my blog under my username... and to do that, you have to code the image onto the site so the next time it scans the page, it sees the link and confirms that you own the thing.
So yup! That's what that is.