Handwriting detectors implemented by the Postal Service. My ML professor worked on algorithms with USPS for over 20 years and gave our class a sub-problem for

Handwriting detectors implemented by the Postal Service. My ML professor worked on algorithms with USPS for over 20 years and gave our class a sub-problem for a term project. He once told us a story that the computer scientists were all up in arms because they wanted the post office to design letter boxes on envelopes to encourage people to write their characters in legible english. Obviously that didn't happen and thus it took quite a bit longer to design software that would reliably recognize v's from u's and b's from 6's and r's from t's and c's from a's under the ridiculous constraints that sorting millions of packages of mail requires.