At NOFA-NY last January, I saw this grain mill
demonstrated in a session on home milling. KoMo, a German company, also makes two flakers
(one electric, one manual) as well. The KoMo mill is pricey; it's an import. However, the two people I've met that have one say theirs are 20 plus years old, see daily use and are still going strong.
Whole grain berries will keep for decades if properly stored, but you need to have a way to process (mill or flake) them in your home. Between the mill and the flaker, I don't have to rely on processed grains from the store any longer. Also, freshly ground flour or flaked oatmeal retains more nutrients. Oatmeal groats that are flaked just minutes before going into the pot actually have more flavor, as does the bread you make from flour you can mill yourself.
These devices save oodles of packaging too. No need to purchase small boxes of rice meal (for hot cereal) or Cream of Wheat or corn meal.