Google is preparing to set up a free Wi-Fi service in the US. The popular search engine has filed three patents related to offering wireless internet access. The patents all have to do with serving up advertisements through a wireless internet connection maintained by a third party. Google will be teaming up with internet company Earthlink who will be the ones who will build the actual Wi-Fi infrastructure, and by teaming with Earthlink, Google believes that the wireless network will be completed quicker.