If you have been viewing this blog recently and have been redirected to some advertisement site like search.goodcarquotes, or had a pop-up, or seen the Clicksor ads in the left bar, I would like to apologize. I had noticed them myself before, and finally took the time to track them down. It seems the Sociable gadget (that showed submit-this-page-to-various-social-networking-sites buttons) is bad. I have removed it, and I hope I've cleaned up the situation.
Thanks to Nitecruzr on the Google product forums for the answer. (Note that the specific advice is only applicable to my layout.) For reference, see Blogger Blogs Being Hijacked By The Sociable Gadget.