In 1998 Chris Eccles, a physics researcher, sent a post to sci.physics.electromag forum. He details an experimental machine he constructed, in order to show that only cranks could believe that spinning a few magnets can create strange and seemingly impossible effects.
His machine was an electrically driven disc with magnets around the circumference, enclosed within a frame containing opposing magnets. CRT screens on computers, and fluorescent tubes behaved abnormally, and he measured a 4% weight loss of the apparatus. The details can be found here.