BYOB: Bring Your Own Bag. Simple idea. Difficult to execute. I've got several reusable shopping bags and about half the time I run out the door to go shopping and forget to take them to the market. But I'm getting better. And so are some retailers.

Whole Foods announced today it's going to stop using plastic shopping bags by Earth Day, April 22. And for one day only, today, it is giving away reusable bags. I hope it keeps a spotlight on that goal, so that this doesn't just lead to a spike in the use of paper bags as replacements. What percentage of people bring their own bags to the market? I'd take a wild guess and say it's probably under 2 percent, but maybe this will help it grow. It's an easy fix, even though behavior is hard to change.

"...We estimate we will keep 100 million new plastic grocery bags out of our environment between Earth Day and the end of this year alone," Whole Foods President A.C. Gallo said.

- Samuel Fromartz