Adventures of a Thrifty Mommy has a great tip on how to reuse cereal bags! The bags can be used to make cracker crumbs or to crush nuts since they are strong enough for a rolling pin. It's a lot cheaper than using ziplock bags! I just wasted a ziplock bag crushing graham crackers the other day! (sheesh)
Adventures of a Thrifty Mommy has over 140 thrifty tips!