[…]This PayPal vending machine on exhibit at the PayPal X Innovate 2010 developers conference was created by Ray Tanaka and his crew at PayPal Labs.

They hacked together the multi-part system using a mechanical candy dispenser, a couple of Arduino Duemilanove, a WiShield, relay, proximity sensor, and LED display.

The end result allows you to scan a QR code, make a payment, and acquire munchies using a smartphone. As you make your payment, the machine will tweet your purchase and notify a confirmation display.

via [helablog]