ChesS

Is a game which is some thousend years old.
It is especially popular for it's complexity.

the world organization of chess players is the [http://www.fide.org FIDE] 

all you need is:
* two players
* chessboard with figures
* optional watch

unfortunatly the rules are to complicated to describe here
a lot of more-fun-more-beer-less-thinking variants emerged. 
but i don't know the english terms