Not quite in the engineering, but fascinating nevertheless. I was just browsing the Marine Log and came across this.
A German company that produces wind farm hardware is investing in a freighter that is partly propelled by four Flettner Rotors.
Flettner rotors are large cylindrical rotors that use the Magnus effect, where a spinning body in a moving airstream experiences a force perpindicular to the direction of the airstream.
This is not new technology, a experimental ship was built in 1926 in Germany. The Barbara was fitted with 55 feet tall hollow cylinders, 13 feet diameter and driven by electric motors

http://www.shipsnostalgia.com/gallery/s ... dition=and