Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsTwisted Surfaces of Revolutionhttp://demonstrations.wolfram.com/TwistedSurfacesOfRevolution/]]>http://demonstrations.wolfram.com/TwistedSurfacesOfRevolution/Discus Flighthttp://demonstrations.wolfram.com/DiscusFlight/]]>http://demonstrations.wolfram.com/DiscusFlight/Penrose's Train Challengehttp://demonstrations.wolfram.com/PenrosesTrainChallenge/]]>http://demonstrations.wolfram.com/PenrosesTrainChallenge/Pseudosphere Geodesicshttp://demonstrations.wolfram.com/PseudosphereGeodesics/]]>http://demonstrations.wolfram.com/PseudosphereGeodesics/Surfaces of Revolution with Constant Gaussian Curvaturehttp://demonstrations.wolfram.com/SurfacesOfRevolutionWithConstantGaussianCurvature/]]>http://demonstrations.wolfram.com/SurfacesOfRevolutionWithConstantGaussianCurvature/Hyperboloid Geodesicshttp://demonstrations.wolfram.com/HyperboloidGeodesics/]]>http://demonstrations.wolfram.com/HyperboloidGeodesics/Cone Geodesicshttp://demonstrations.wolfram.com/ConeGeodesics/]]>http://demonstrations.wolfram.com/ConeGeodesics/