Check that your Google ad opt-out has been honoured

I have opted out of Google’s Doubleclick (and others’) advertising cookies many times. In theory, you only need to do it once, but I have been to Google’s opt-out page many times to find that the company has set another new cookie on my system.
   I fiddle around with my cookies a lot, so I’m not going to blame Google for another privacy gaffe this time. In the past I have deliberately opted out and opted in, just to check the accuracy of its targeting (it’s not that good), but lately I made the decision to keep the Doubleclick cookie permanently off my computers. But I urge those who think they have already opted out of Google’s ad-targeting to check. It wouldn’t be the first time it sprung unexpected privacy settings on us, Facebook-style.
   Head to Google’s home page and click on the Privacy link at the bottom. Then click on Advertising in the left-hand column. Or go directly to the ad preference page here.
   You can opt out of other Network Advertising Initiative members’ cookies—there are 61 at the time of writing.