Wind speed. Will your kite lift your camera?

Here on the Space Coast I use flags to help me judge wind speed.  Whether or not my kite will lift my camera or merely drag it along a grassy field, unable to lift it, can often be easily foretold by the flutter of a flag on a pole.  Wind direction is easily observed by the waving of a flag.  Flags are everywhere, from  gas stations to schools, to the post office; they are easily spotted from almost anywhere.  With a little bit of trial and error one can quickly learn to judge his or her kite's lifting ability in any given wind by the intensity of a flag's flutter.

What other methods do you use to judge wind speed and to know if there's enough wind for your kite to lift your camera?