I found these little gems on a pretty obscure website back when I was still nursing my first little one. I was tired of the shields that you stick in your bra to prevent "lactic leakage". They are bulky and show through your clothes and you have to change them out all the time.
Lily Padz actually stop the flow, hold the excess leche and can stand in for a bra on strapless dresses and such. I have purchased two pairs even since I've stopped nursing just to wear with tricky dresses or swimwear to prevent highbeams. They are a life saver during nursing, I wore them around the clock to prevent leaks. (There is nothing weirder than waking up in a puddle of milk)
(Side note for new Moms to be - when/if you are breastfeeding, sometimes leakage can be a problem. At first it is very difficult to control and happens consistently, eventually they become trained and only produce when you are nursing your baby. To prevent unexpected leaks you wear absorbant pads in your bra. These are the things that nobody tells you about in preparing for motherhood! )