Maybe I'm slow off the mark but I just now, for the first time, heard of something called 'dynamic pricing'. Apparently it started with the airline industry but is now, thanks to Google, supposed to be common for much on-line advertising. What it means is that your interests are tracked and when you click on an ad, the price you see depends on how badly the advertiser thinks you want it. If your interest is assessed as high, you will see a higher price than your more casually clicking neighbour.
The other day, I saw a post from someone on the Geekzone ads thread who said he actually appreciated advertising and often bought things. Guess what, sucker? Your clicks are costing you money. This kind of behaviour is why I am convinced most on-line advertisers are mean-spirited privacy-violating dishonest scum who will use any trick at their disposal to suck money from their victims. Some people are quick to say advertisers pay for all those wonderful Internet goodies we enjoy, but that is how the Internet started out anyway. Things were free, people enjoyed sharing their creations and knowledge, and there was a great spirit of camaraderie and being part of something special. No-one needed ads for that.