While in the drive-thru at a fast-food restaurant in America, one man's random act of kindness resulted in more than 900 cars taking part in the pay it forward chain.
Early this week one man drove to the drive-thru of a Dairy Queen in Minnesota, offering to pay for his meal and for the meal in the car behind him.
Tina Jensen, the Dairy Queen store manager, told CNN it often happens once in a while but at most it lasts for 15 or 20 cars and then fizzles out.
However, this time Jensen was wrong.
Over two and a half days, the pay it forward chain continued with, more than 900 cars taking part.