> do some searches on mattresses and see what ads you see over the next weeks. This sounds like an interesting experiment. I mean, the result seems obvious for

> do some searches on mattresses and see what ads you see over the next weeks. This sounds like an interesting experiment. I mean, the result seems obvious for a search on mattresses, but I think we can expand on this to search for more controversial or political topics. I'm going to start planning this experiment and I'd be very interested if anyone knows of an existing study along the same lines.