Green doesn't do much for the model below because her eyes are also green, hazel-eyed beauties should try green mascara to bring out the green in those eyes.
Blue is the color most people use, it stands out the most and can match with anything you wear. It looks good on all eye colors especially brown. To make it stand out even match your mascara with a pencil eyeliner, not the same color eyeshadow. I recommend Diorshadow Mascara in Azure Blue.
Purple mascara looks best on green eyes. Make sure to layer on the color on so that it shows.