Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsRandom Closed Meandershttp://demonstrations.wolfram.com/RandomClosedMeanders/]]>http://demonstrations.wolfram.com/RandomClosedMeanders/Permutation Grid Classeshttp://demonstrations.wolfram.com/PermutationGridClasses/]]>http://demonstrations.wolfram.com/PermutationGridClasses/Open Meandershttp://demonstrations.wolfram.com/OpenMeanders/]]>http://demonstrations.wolfram.com/OpenMeanders/