Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsTorus in Nil-Spacehttp://demonstrations.wolfram.com/TorusInNilSpace/]]>http://demonstrations.wolfram.com/TorusInNilSpace/Numerical Iso-Optic Curve of the Ellipsehttp://demonstrations.wolfram.com/NumericalIsoOpticCurveOfTheEllipse/]]>http://demonstrations.wolfram.com/NumericalIsoOpticCurveOfTheEllipse/Geodesic Cone in Nil-Geometryhttp://demonstrations.wolfram.com/GeodesicConeInNilGeometry/]]>http://demonstrations.wolfram.com/GeodesicConeInNilGeometry/Iso-Optic Plane of the Regular Tetrahedronhttp://demonstrations.wolfram.com/IsoOpticPlaneOfTheRegularTetrahedron/]]>http://demonstrations.wolfram.com/IsoOpticPlaneOfTheRegularTetrahedron/Iso-Optic Curve of a Regular Polygonhttp://demonstrations.wolfram.com/IsoOpticCurveOfARegularPolygon/]]>http://demonstrations.wolfram.com/IsoOpticCurveOfARegularPolygon/Geodesic Balls in the Nil-Spacehttp://demonstrations.wolfram.com/GeodesicBallsInTheNilSpace/]]>http://demonstrations.wolfram.com/GeodesicBallsInTheNilSpace/Iso-Optic Curve of the Ellipsehttp://demonstrations.wolfram.com/IsoOpticCurveOfTheEllipse/]]>http://demonstrations.wolfram.com/IsoOpticCurveOfTheEllipse/Horosphere Packings of the (3, 3, 6) Coxeter Honeycomb in Three-Dimensional Hyperbolic Spacehttp://demonstrations.wolfram.com/HorospherePackingsOfThe336CoxeterHoneycombInThreeDimensional/]]>http://demonstrations.wolfram.com/HorospherePackingsOfThe336CoxeterHoneycombInThreeDimensional/