Is Google Listening In?
He first just wrote a subject on a piece of paper and then proceeded to visit a site that had a list of links to others. He visited several others and just saw random ad's come up. Then he vocalized what he had written down and proceeded to talk about the subject that was "Dog Toys", saying he should get some for his obedient dog, like he was having a conversation about the subject.
He then revisited these sites and all bar one had ad's for dog related products on them.
I suppose this is something you could try out for yourselves.
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