8. A few years ago when I was taking an Elementary Chinese class I learned that 8 is a very lucky number over there, while "4" is considered very unlucky because the pronunciation for it, "si (say it like "suhh")", is eerily similar to that of the word for "death" (the character for 4 is "四" while "death" is "死") There are many theories on why the number 8 is considered lucky, but it's really shrouded in mystery at this point.
So my birthday is 08/08, which means I'm considered a pretty lucky person if I go to Beijing! They are very fascinated by luck. X3