what do you mean?? the currency that have similiar move or the currency that effect the other currency? ..what ever it is i try to give u both.
the currency usually that have similiar move is gbp/usd to eur/usd,us-jy to us-chf, wll that's the major currency.
the currency that effect the the other usually from major to cross currency.like gbp/usd and usd-yen movement will effect bp/jy.which one give the bigger effect? i think us-jy.bcoz the higher value of currency..(err..i mean like this..gbp value will be 1.9620 for example and us-yen value will be 121.81 for example so u can get the bp/jy price by 1.9620 X 121.81=238.99.so u see..gbp only 1.9something and us-jy 121.something.us-jy become the bigger factor on this math operation.errr..geezz i'm not good at explanation but i hope u get what i mean and i hope it can answer ur question.