We've been selling fashion-forward reusable shopping bags for several years now. We prefer the kind that you can stow inside your (Laura Bee) bag so that you don't accidentally leave it at home or in your car.
Recently a loyal customer told me about Flip & Tumble bags, which come in bright rip-stop nylon, and collapse into cozy little balls pouches that can also be used for juggling demos at the farmer's market.
We have these babies in a small lunch size, and a roomy grocery/beach version. Prices range from $7.50-$12.