This is simple,I say a word and you post the first word which pass in your head.
For example:
I say "Grass"
You say "Park"
An other person says "Central Park" and so on.

Paul McCartney and John Lennon
http://fr.youtube.com/watch?v=1akCkkgOIkc¤She don't lie,she don't lie,she don't lie...cocaine!¤
Clapton is God!