Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsCompound-Hemisphere Reflector (Cat's Eye)http://demonstrations.wolfram.com/CompoundHemisphereReflectorCatsEye/]]>http://demonstrations.wolfram.com/CompoundHemisphereReflectorCatsEye/Dynamic Billiards in Ellipsehttp://demonstrations.wolfram.com/DynamicBilliardsInEllipse/]]>http://demonstrations.wolfram.com/DynamicBilliardsInEllipse/Retroreflective Spherehttp://demonstrations.wolfram.com/RetroreflectiveSphere/]]>http://demonstrations.wolfram.com/RetroreflectiveSphere/