The golden ratio is a number, approximately 1.618, which when considered as
a ratio posseses many interesting properties (Wikipedia). The wicked thing
about this ratio is that it is seen all around us. Many natural phonomenon,
such as the way petals grow in a flower, the way seashells are made, or the
way in which large groups of trees spread out through a forrest are all
guided by this “magic” number. It’s highly cool. Here are a couple of
illustrations:

Phi to 1000 characters:

1.618033988749894848204586834365638117720309179805762862135448
622705260462818902449707207204189391137484754088075386891752
126633862223536931793180060766726354433389086595939582905638
322661319928290267880675208766892501711696207032221043216269
548626296313614438149758701220340805887954454749246185695364
864449241044320771344947049565846788509874339442212544877066
478091588460749988712400765217057517978834166256249407589069
704000281210427621771117778053153171410117046665991466979873
176135600670874807101317952368942752194843530567830022878569
978297783478458782289110976250030269615617002504643382437764
861028383126833037242926752631165339247316711121158818638513
316203840052221657912866752946549068113171599343235973494985
090409476213222981017261070596116456299098162905552085247903
524060201727997471753427775927786256194320827505131218156285
512224809394712341451702237358057727861600868838295230459264
787801788992199027077690389532196819861514378031499741106926
088674296226757560523172777520353613936