The fact that we're all akin to lumbering flesh robots designed to help our genetic material persist. That was kind of humbling.
http://www.amazon.com/Selfish-Gene-Anniversary----Introducti...
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Biology in general is tremendously useful in providing you with a whole set of patterns and models of "things that work" (in the proper context, of course). Studying some college level general biology is recommended if you haven't already.