If you've ever had a Facebook friend in need of some money, you may soon have a way to pay them without much fuss. Stanford student Andrew Aude has shown off hidden code in Facebook Messenger's iOS app that will let you send funds much in the same way that you share a photo; you just have to add a payment card and a PIN code. The transaction is private and appears to be free at the moment, although it won't be surprising if Facebook eventually takes a small cut of each transfer.