About sensing weather, a group at my university developed a sensor based on
temperature differences:
    S
  S R S
    S
A resistor (R) warms the air above it, the four temp sensors (S) measure the
difference, giving both wind direction, speed and ambient temperature.
All integrated on one chip. Can be compensated with humidity.

http://www.hsa.lr.tudelft.nl/~bvo/research/sensor.htm (sorry, no good info on
WWW.)

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