Part of staying on or under budget has been making some of the foods we used to buy from scratch. Tortillas, syrup, and croutons all turned out very well. I think we're going to start baking bread ourselves, too.
The other (major!) part of our grocery-store-economy is that we have a freezer full of venison. Working that into meals sure drives the cost down. My plan (hope?) is that we will be under budget so consistently that when we do finish using the venison, we will have a kitty to spend on a side of beef or some other comparable large amount of meat for the freezer.
Now if we could just be more disciplined about our entertainment budget, we'd be doing great!