Maersk installed 100-foot-tall rotating sails on one of its tankers
It's called the Flettner rotor, it uses the Magnus Effect. Cool stuff but not exactly new tech. It gives a nice read, here's some links to wikipedia on the topic: https://en.wikipedia.org/wiki/Magnus_effect and https://en.wikipedia.org/wiki/Rotor_shipI'm curious of what will be the results.