My laptop caught one an hour ago which scared the **** out of me. It was just a blue page with white text saying 'your computer is in danger/your personal details are at risk' or something, can't remember because of the panic... there was also a voiceover repeating it (does this sound familiar?) Did the usual take the battery out, put it back in, start up Windows in SafeMode and system restore procedure. So far everything seems normal, hoping it was just one of those fake viruses that's designed to scare the shit out of you.

I don't use my virus protection (McAfee) which is stupid, I don't trust it and it makes me even more paranoid. When something like this happens I just ignore it and hope it doesn't come back, which usually seems to work.