Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsSnell's Law of Refraction (Wave Fronts)http://demonstrations.wolfram.com/SnellsLawOfRefractionWaveFronts/]]>http://demonstrations.wolfram.com/SnellsLawOfRefractionWaveFronts/Paperfolding Dragon Curvehttp://demonstrations.wolfram.com/PaperfoldingDragonCurve/]]>http://demonstrations.wolfram.com/PaperfoldingDragonCurve/