Report popups, annoying/inappropriate adverts here Answered
I just had a persistent popup (the sort that follow the screen as you scroll up and down) from sustain lane, asking me to take a survey for safecount.net/questionmarket.com. The advert also appeared in the sidebar (the text "Take a survey" on a magenta background).
If there's a duplicate of this thread somewhere else, I couldn't find it (apart from gmjhowe's thread about the nudity ones). If not, might I suggest a sticky with a title like the above to provide one place for people to report adverts?