In-flight wi-fi service seems to be the coming thing…and at least one airline (Jet Blue) is experimenting with making it free. For the ones that charge, the rates look like they'll be around $5.95 for short flights and $12.95 for flights of three hours or longer. Obviously, this is fine for those who need it, and perhaps there'll come a time when I will. But there are also times when it's kinda nice that for the length of your flight, your phone is off and nobody can reach you…