well, i was just messing around with psuedo genetic programming, and had 30 arrays of the possible characters in a larger, and needed a rating for each one, so i decided i would either have the array of 30 possible character arrays, and another array that contained the rating for each item, i.e $rating[0] would be the rating for $possiblechar[0] (which is an array). I thought i could avoid the problem of making sure they were sync-ed by having a hash with the reference to the each array of possible characters be the key, and the pair for that key be the rating. That way there wouldn't be any problem making sure they were sync-ed or dealing with more then one data structure. Maybe not the smartest way outside of the fact that perl doesnt allow you to use array references as hash keys