If the item you are making is savory rather than sweet and wouldn't taste right with applesauce, use mashed potatoes instead. In the meat department, substitute ground turkey for hamburger. Your family will never know the difference, it is much lower in fat, and very economical. Look for it in the frozen foods section. Eat more fruits and vegetables for snacks.
Bread is also low fat and makes good snacks.
Cereal is lowfat and makes a good snack also. Plain old Jello is also fat free. Make your own pudding and leave out the margarine. Instead of buying fat free ice cream, buy sherbet. Instead of frying things, just spray a non-stick skillet with Pam.