Probability Calculator

I've got two kids that kind of defy genetics.  Both my wife and I have brown hair and darker eyes.  We have two kids that have blonde hair and blue eyes.  It would be totally awesome if there was a online calculator where you could plug in your physical characteristics and those of your significant other and then it would spit out probabilities of your children having certain traits.  For example I have brown hair and my wife has brown hair and out of our parents only my wife's mother had blonde hair as a child (it went brown with time).