Mueller, Richard. "Age of Miracles"
Divergence: c 1450 CE
What if: The industrial revolution began in the middle of the middle of fifteenth century Italy.
Summary: In about 1500, a computos salesman gives a demonstration to the pope, knowing that failure to make a sale will likely mean falling in the hands of the Inquisition.
Published: The Magazine of Fantasy and Science Fiction, September 2005.