Oh, could there be something that is not showing up in the logs, as this only just started happening and it is very invasive as I browse. I do have a Firefox add-on called Video AdBlock 3.0 that is enabled, but it doesn't seem to work, even on videos.
I have copied the URLs of some of the sites I get redirected to, would you like me to paste them in a reply to you, or would that not be safe?