I made a humidity gauge that gets its info from wunderground.com, and displays the relative humidity on an analog clock face.

Inspirations:

• The Weasly clock in the Harry Potter books and movies – an antique analog representation of data collected by some non mechanical means.
• This raspberry pi stepper motor project that provided a hefty chunk of the motor control code and the initial wiring diagram
• The “Internet Umbrella Rack” project in chapter 10 (Python and the Internet) of the excellent book “Getting Started with Raspberry Pi” by Matt Richardson and Shawn Wallace

Interesting components of the build are:

• A hand built circuit board with 1) a header for the GPIO ribbon cable from the pi, 2) a socket for the 18 pin Darlington driver, 3) a header for the unipolar stepper motor connector, 4) two pairs of terminals tied to input pins with pulldown resistors to ground for the momentary switches serving as calibration buttons
• A Model A Raspberry pi
• An Element 14 Wi-Pi wi-fi adapter for wireless connection to the LAN/Internet gateway
• A 512 step (geared) 5 volt unipolar stepper motor
• A Darlington driver chip
• A broken mantle clock
• A custom clock face created in inkscape

Pictures:

Get the code!