Here's a substitute for mothballs that will work just as well and leave your clothes smell nice instead of like a chemical plant.

Save your soap slivers that you would normally throw out and allow them to dry. Get a plastic bag and poke a bunch of holes in it. Put the soap slivers in the plastic bag and you've got yourself a substitute for moth balls. You can get some really nice smelling soaps, and your clothes will smell nice and clean when they come out of storage.