On a recent Monday morning, I found myself comparing aromatic notes with a true connoisseur of sorts.

When you're in this business, you know, you have a lot of opportunities to smell things.

They each have a very unique aroma.

I've often thought to describe it the way wine is described.

Mountain Lion is my favorite.

It has a very unique burnt umber smell.

The wolf has the darkest color.

The smell is rich, and it has, I would say, notes of earth.

You make it sound so great.

Well, I can't help it, you know, in a crude way. To me, it's the smell of money.

This expert, smeller, his name is Ken Johnson, but in certain circles, he goes by a different moniker.

Well, I'm known as the Pea Man. I started and operate predator p.com.

Johnson sells a product that is generated every day in huge quantities.

Most of us think of it as waste, but where one man sees animal urine, another man sees treasure.

It's really the ultimate recycling.

You take something that would normally be just disposed of and put it to work in a way that's natural.

For the Freakonomics Radio Network, this is the Economics of Everyday Things.

I'm Zachary Crackett.

Today, animal urine.

As a kid in New Jersey, Ken Johnson loved the outdoors.

The first chance he got, he moved to one of America's most rugged states to study forestry

at the University of Maine. After school, he stayed up there. He found his way into the ad business

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