I'll never forget that guy. There we were, selling lemonade on the side of the road. Twenty-five cents a piece. We had already made a few bucks for a few hours work. Not too shabby.

But that guy—well, he just changed everything.

The car slowed as it came towards us. Another customer. Nice.

I don't really remember what he looked like, but I remember the smile. Warm and friendly. He asked us for a cup of lemonade with that smile. How could we say no?

We had a quality operation going. One person poured the lemonade. Another one gave it to him. I took the money. It clicked like clockwork. We were all over that action.

We gave him the cup. He flashed us that smile again. He reached down to grab something from his car. I remember him ruffling through something, maybe his wallet. He finally seemed to find what he had been looking for.

And out it came.

A bill. A bill! We expected him to ask for change. We didn't want to get our hopes up. Still, we stood with bated breath. I, as the consummate professional, made sure to smile and take the bill. I waited for him to put his hand out for the change.

Instead, he smiled at us and waved.

"Have a good day, kids," he said. (Something like that, at least.)

I went over to the table—to my friends—to celebrate. We had just been paid for four lemonades when all we'd made was one. Amazing.

And that's when I took a look at the bill. Something about it looked strange. I was mostly used to bills with George Washington on the front, but this one had someone else. Some stuffy dude with facial hair. Who was he?

But what ended up catching my eye in the end was the number on the corner of the bill.

Five.

For a moment, I thought something was wrong with my eyes. I checked again.

Five.

I stared, flabbergasted. Was this possible? Had all my years of lemonade production finally paid off?

I showed my friends and we all stared with disbelief at the bill. Five dollars. Five dollars!

It was the best day of our short lives. Even better than the day we got a bicentennial quarter.

I'll never forget that day. How happy we all were. How we smiled and showed off our fancy new bill to our parents. The way we strutted around like we were the kings of the side of the road. Life was glorious on that day.

I still remember that guy who stopped for us. How he smiled like it was nothing to give a few kids a five dollar bill just to make them happy. I wonder if he knew how happy it would actually make us. How I'd still remember him twenty years later—probably for the rest of my life. I wish I could tell him.

Whenever I see a lemonade stand now, I make sure to buy some lemonade. I never pay with coins (I hate 'em anyway). The kids smile. And I remember the guy's smile. Somehow, they seem connected.

They say that if you save someone's life, you save the world. Well, sometimes you don't need to save a life to change the world. Sometimes you just need to buy some lemonade.