Drive-by compliments make strangers smile

The plan was simple one: Compliment strangers and make them smile.

"We jumped in a car and yelled nice things to people... We even used a megaphone!" wrote YouTube comedian Blake Grigsby.

Grigsby drove around the streets of Chicago in a convertible, shouting compliments to unsuspecting citizens, hoping to make their day.

The strategy worked. Instead of ignoring Grigsby's loud praise, people responded with huge smiles, thumbs up and thanks.

"Your hair reminds me of a sunrise and it is quite awesome," Grigsby told one stranger.

"You are a very handsome man," he told another.

To a couple walking down a sidewalk together, he shouted: "You guys are a cute couple! That is so cute!"

And when he spotted a man reading new listings in a realtor's window, he offered some encouragement: "You're an excellent reader, sir. Excellent."

He even got a little romantic: "I hope you're a part of my never-ending story, sir. You're a very handsome man."

Watch additional footage of the drive-by compliments here.

This isn't the first time Grigsby's screamed sweet things at people. Watch last summer's "aggressive compliments" below:

And these compliments are more than just a nice gesture: It's been found that getting a compliment can actually improve your mental health.

According to a 2012 study published in the journal PLOS One, receiving a compliment can improve motor skill memory, just as receiving a cash reward does.

In one exercise, researchers found that study participants who were complimented after learning a new skill performed the same exercise significantly better the next day than those who hadn't received direct compliments.

According to Professor Norihiro Sadato, the study lead and professor at the National Institute for Physiological Sciences in Japan, "To the brain, receiving a compliment is as much a social reward as being rewarded money. We've been able to find scientific proof that a person performs better when they receive a social reward after completing an exercise. Complimenting someone could become an easy and effective strategy to use in the classroom and during rehabilitation."

Given any good compliments lately?