Starbucks customers can now "pay it forward" on their cellphone

Mobile developer Jonathan Stark wants you to use his Starbucks card; really! A screenshot capture of his card in the Starbucks iOS app is available from his website, and anyone can download this and save to their phone. The image will work just like it would if it was the actual app at any Starbucks register. Stark also wants to learn how people will share physical goods digitally and is...