If you can afford one, a deep freezer is a good investment. If you have the extra storage space you can load up on meats and frozen entrees that are on sale.
One other money saving tip is to buy meats and fresh vegetables that are reduced because will soon go bad. Now, if you plan your meals in advance this won't help you but if you're versatile, you can get expensive cuts of meat for half the price and eat them for dinner that night or the following night.
My last tip is to shop at the Dollar Tree, Mighty Dollar or 99-cent store in your area. I can get a three pack of Ivory soap, name brand dishwashing liquid, and name brand toothpaste for a dollar. If purchased at the grocery store, these items would cost me nearly three times as much. I know most people don't have time to run all over town to get these things so I only go once every month or once every other month and I get more than enough to last me until I go back.