What are the best Arduino starter projects?
jws: I would suggest it is whatever feeds your dreams. Many things are possible, the only caution is to make your first step doable. How about you tell us what you think would be cool and we could suggest how big the first step should be?(For reference if you need help getting started: things I've made from Arduinos...  analog meter display for a bank for T1 network loads
  cylon pumpkin (laugh, but eventually everyone makes one)
  ambient light sensitive LED, using the same LED for sensing as making light
    (pretty nifty trick, makes me wonder my more electronics 
     don't do it. No need for blinding indicators in a dark room)
  2d ultrasonic anemometer
  weather station
  wireless network from ISM band ASK radios
    (worked, but integrated solutions are probably better)
  DC power controller/rationer for solar powered unmanned remote telemetry system
  DC motor controller for http://8ball.lunarware.com 
    (not online yet)
  Multichannel temperature monitor for a cranky air conditioner
    (lots of data, no idea how to interpret, a lesson there somehwere)
  Tiny LED xmas tree for my daughter, 
    red LED ornament blinks secret message in morse code
  Multi channel servo controller from a PWM LED driver.
  USB low speed interface with just a couple pins and resistors.
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