We don't know what it is about the sugary slice of heaven known as donuts that inspire generosity in humans, but inspire it did. A drive-thru customer at Heav'nly Donuts in Amesbury, Massachusetts, started a "pay it forward" chain that lasted 55 people in a row:
“After that it was like, oh we’re three cars deep, four cars deep, and after about the 15th car I started letting the customers know, ‘Hey, we’re 17 cars in, you can either keep it going or you can take your coffee and go. Either way it’s your choice,’” the clerk said.
According to the clerk, 55 customers rolled through the drive-thru back-to-back, each one paying for the next order.
The chain only broke when they ran out of customers: Link