Suppose you were browsing the internet of your cell phone as you are walking down a street. As you pass a store, the ad you see on your phone is for that store you just passed. Such technology is already available, but on February 23, 2010 Google was awarded the patent for the idea. It is patent number 7668832.

The paranoid out there may wish to avoid such ads. You can. Many cell phones today have GPS built-in. You can turn the GPS off. Your general location can be determined using the location of the nearest cell phone tower. But the only thing that will be known is that you are somewhere in range of that tower. An exact location is impossible. A cell phone's location can be computer using triangulation, but is not something a cell phone can do. You need at least 3 towers for that, but a cell phone locks in to one tower. So if you turn off your phone's GPS antenna, you will not get ads targeted to where you are at right now, such as in the situation above.

Your general location can also be determined by the information that is required for the internet to work. This cannot be connected to the physical location of the internet connection without your ISP's permission. That is likely not to happen. Still, ads can at least know a general location. I've already seen ads that talked about deals in Raleigh (although Raleigh is 45 minutes away). With this patent, all such ads will now have to pay royalties to Google or stop determining your general location. There is really little you can do about that.