You've seen those "take a penny, leave a penny" trays at convenience stores. What if you could do the same thing with coffee?

That's what Jonathan Stark aims to find out in a social experiment called Jonathan's Card -- and if you have a smartphone, you can play along. Just save a picture of his Starbucks card (below) on your phone, and the next time you make a run to the coffee behemoth, pay for your beverage by holding that picture in front of the barcode scanner at the register. If there's a balance on the card, your caffeine fix is covered.

Of course Jonathan isn't footing the bill himself -- he's relying on random acts of kindness from strangers to keep the card loaded with funds. And it seems to be working. The Twitter account that tweets out automatic updates of the card balance, @jonathanscard, shows people are indeed building good karma by adding to the balance, and the experiment's Facebook page has lots of folks talking about it.

We're kind of loving this -- if for no other reason than it serves to renew our faith in humanity, one latte at a time.


Jonathan's Card

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