Reusable grocery bags are a good buy.

I while ago our grocery stores started marketing and selling reusable cloth bags. They generally sell for about $1 each. They are large sturdy bags that easily replace the standard paper or plastic grocery bags. Plus our grocery store gives us 5¢ off for each bag we use. If you go to the grocery store about weekly you're saving about $2.50 a year for a $1 purchase. That's a 250% return on your money in a year. The only downside is that I occasionally forget the bags, so I just keep them in my car.