Sometimes because of adoption or a health issue with the mother (taking certain medicines, for instance) a mom can't produce safe milk for her baby. The mom can be stuck thinking that her only option is now formula feeding.
Chris commented on my post about the breastfeeding class I went to, and she reminded me that I wanted to talk about donating milk for this kind of situation. This is SUCH a good thing to do! Nursing moms operate on supply and demand, so if you plan it properly and pump between feedings, it's totally possible to have enough milk to feed your own baby AND to donate.
The really important thing to realize is that a baby benefits by having real human milk even if it's not from the baby's own mom. Even if you only get an ounce or two per day of extra, that's a little benefit for someone's baby that wouldn't have happened otherwise.
I found out after the class that there is actually a milk donation center being set up for New England, and that I can be connected up with them so I can participate in their program if I want to. I haven't found out much more than that yet, but I will be, and will post what I find.