Online slide rule: http://www.engcom.net/index.php?option=com_sliderule&Itemid=73 http://www.engcom.net/index.php?option=com_sliderule&Ite... Always thought I

Online slide rule: http://www.engcom.net/index.php?option=com_sliderule&Itemid=73 http://www.engcom.net/index.php?option=com_sliderule&Ite... Always thought I should buy a slide rule and learn to use it so if I'm still around when civilization falls... (I know some might argue that event has already happened.)