I'm jumping on the bandwagon here, since in the current economy most are trying to pinch pennies wherever they can. Often, the grocery bill is the only flex people have in their budgets. The Toronto Star discusses 5 meals under $5 (Canadian) each also with 5 tips for stretching your food budget.
Finally, the USDA has created a helpful resource for creating meals to fit your budget at their Recipe Finder. Here you will find a form where you can enter the ingredients in your kitchen to search for nutritious recipes, or simply put in a dollar amount and it will bring up recipes that cost that amount or less per serving. You can even search by what appliances you have available--so it can be a cost effective option for cooking while traveling.
What have you found to help you save money in the kitchen?