This technology is moving forward. But from a wifi signal?? Hope it works. The only time I stay in one place long enough for such a gadget to charge anything would be at night. And then I'm either in a motel/campground with outlets, or too far in the boonies to catch a signal. Now from a cell tower, that could be very useful.

http://money.cnn.com/magazines/busin...04/01/8403349/