Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsDust with Line Shadows in Every Directionhttp://demonstrations.wolfram.com/DustWithLineShadowsInEveryDirection/]]>http://demonstrations.wolfram.com/DustWithLineShadowsInEveryDirection/