I'm being redirected at anytime, it can be from a bookmark page, from typing on the address bar, from a Google search, it doesn't matter but it is getting very annoying.
I changed my DNS to an openDNS, but the problem persisted. I installed and ran ClamXav, it didn't find any malware or problem. I decided to create a new airport connection with openDNS. The problems is still going on.
I deleted cookies and reset firefox, but after a couple of hours the problem was back.
It's interesting that the problem went away for a few hours after the reset. One of the primary changes is that Firefox does not have any Extensions after a reset. Could you check on whether any have been added since then?