If I go to Starbucks (one that supports it) what is a typical charge? (I assume that is determined by the market.)

The reason that I brought up the question is because I saw an interview with a man on TechTV who had taken a trip across the USA and never needed a dial up or physical connection. I never assumed that I could just take this card with me and use it on exsisting networks.... maybe that is due to my lack of experience with DHCP.