If you were planning on staying at the Courtyard Marriott in Times Square, it looks like you're now safe to use the "free" Wi-Fi. Web developer Justin Watt found a few days ago that the internet service at the hotel inserted code onto every page he visited with the goal of showing ads to him. Marriott told The New York Times today that it has disabled the feature at both the Times Square hotel and a nearby Residence Inn. The hotel chain claimed that neither it nor the hotel itself knew of or approved of such practices, and the company said that it would remind its franchisees that free Wi-Fi must be free in every sense of the word. Apparently the ISP that provided the internet service was to blame for using a tool from RG Nets called a "Revenue Extraction Gateway," which is specifically designed to generate income from showing ads to users of free Wi-Fi access points. It's still not clear how widespread the use of such services are, so for now you'll just have to keep in mind that your next public Wi-Fi connection might not be as free as you think.