We've talked about saving egg shells for the garden, but you can also use them in the laundry to whiten your clothes.
This won't replace bleach, but they're an easy laundry boost that's all natural and free. Don't just throw the egg shells into the wash directly, though. Instead, put them in a muslin cheese cloth bag so that the shells don't get everywhere inside the washing machine. I tried this tip and I did notice an improvement in my whites.
Check out some other uses for egg shells by following the link.
10 uses for eggshells [MotherNatureNetwork]