In this video below, miniature balls roll up the slopes just as if they were pulled by a magnet. This behavior seems impossible as it defies gravity, and the magnetic forces can’t help, as the balls are made of wood! I can assure you there are no fancy computer graphics. Just cardboard, glue, and some wooden balls. It’s a real scene, indeed!Check this out:
http://www.moillusions.com/2010/05/video-impossible-slopes-illusion.html
