Outside In

The computer animation Outside In explains the amazing discovery, made by Steve Smale in 1957, that a sphere can be turned inside out by means of smooth motions and self-intersections. Through a combination of dialogue and exposition accessible to anyone who has some interest in mathematics, Outside In builds up to the grand finale: Bill Thurston's "corrugations" method of turning the sphere inside out.

Official website :http://www.geom.uiuc.edu/docs/outreach/oi/