Amazing Steals at the Grocery Store

One of the downfalls of moving is that you have to restart your pantry from scratch.  I usually try to keep the freezer stocked with sale items so that we are rarely paying full price.  As you can imagine, our freezer is empty.  We had unplugged the fridge when we left so when I say empty I mean it.  With a limited food budget, hubby and I headed to the store.  Stores, really, since we went to multiple grocery stores.
  Many frugal meal planning websites will advise you to build your meal plan around what's on sale, not what you feel like eating.  While I agree with that advise, I also think that if your freezer is stocked with sale items, then when you feel like a certain meal you can just shop your personal store.  When we set out to the grocery store we were not shopping for that night.  We needed to get staples like flour and sugar.  Aside from that, we would pick up whatever was on sale.  At the military commissary, we found pork on sale.  What was usually a cheap cut, we got for even less.  At 97 cents a pound I snatched it up.  The pork is destined for the freezer until we feel like using it.
  Typically this is how I try and keep our grocery costs down.  At Safeway, there was a sale on the Fresh Express Salad mixes.  Usually they are $3+ each (for one of the all inclusive bags).  At that price, there is no way we could afford them.  I would rather buy lettuce and make my own salad for half the cost.  However, Safeway had them for 2/$5 or $2.50 each.  I also had a $.55 coupon for one bag.  Safeway doubles coupons under $.99 so my $.55 became $1.10 off.  I could use one coupon for each bag, which meant I paid $1.40 per bag.  That's over half off the usual price, and something we could afford.  (We also planted lettuce in the garden so hopefully we wont be buying salad mixes for too long)
  What ways do you save money at the grocery store?  Do you plan menus around the sales?  around your freezer?  around what you feel like eating?  I would love to hear how other people shop.