Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsSlide Rulehttp://demonstrations.wolfram.com/SlideRule/]]>http://demonstrations.wolfram.com/SlideRule/Addition Slide Rulehttp://demonstrations.wolfram.com/AdditionSlideRule/]]>http://demonstrations.wolfram.com/AdditionSlideRule/