This is an interesting social media, social experiment. Jonathan Stark is the man behind the idea. What he has done was to buy a Starbucks Gift card, then posted the smart phone payment code on his site, jonathanstark.com/card/#give-a-coffee
If you want a free cup of coffee, download the image to your phone. Go to Starbucks and order your coffee, then when they ask to pay, hold this image up to their scanners. If there is money on the card, then your drink will be paid for.
Jonathan is asking that you also mention him on twitter @jonathanscard with tweets, picks, whatever you would like to share.
The card keeps getting money added to it by people who are willing to Pay It Forward. Some people are transferring small balances they have on their other Starbucks cards and you can also put the card number into the starbucks website and add any amount you wish.
It will be interesting to see how many people, from where participate.