the title says it all :P always wondered that
sometimes google works just as good as a forum, but without the embarrassment of asking...fyi
You have a duct that runs from you eyes to your nose. So when you cry, some of the tears go down that duct to you nose, which causes your nose to run.
Some people actually use their duct for amusement purposes, pushing popcorn kernels up their ducts from their nose and make them come out of their eyes . . . really gross but at the same time cool.
Hope that answers your question.
WTF?! That is... disgusting AND kinda awesome.