A system that uses electromagnets for docking ships is getting ready to be tested at a port in the Netherlands according to this article in the New Scientist. Magnetic docking systems were never used in the past as magnetic fields posed dangers to sensitive cargo like TVs and monitors. Researchers at the Delft University of Technology have developed electromagnets whose magnetic fields do not penetrate far into the ship for this special application. The magnets can be periodically switched off and on rapidly to allow ships to rise and fall with the tide.