This POV Fan Display Hack by Hacking with Gum required a bit of reverse engineering to determine how the device worked in the first place, then a way to re-program the operation of the device to display a new message.
Thanks Craig.
"It turns out that Cenzic made it very easy to access the fan’s EEPROM chip, and with a simple RS232-to-I2C interface you can re-write the EEPROM on this device to make it display whatever you like. "
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Its feature to access the fan’s EEPROM chip is nice
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