Okay, not necessarily a functional Arduino interface per se, but hey - it's delicious!
I made these for my senior project team. (Conor, who is another Arduino forums user, is part of my team.) We're building a wireless EKG and using the Arduino as the microcontroller. I figured that, since everybody in the team has either a Decimila or a skinny or a Freeduino (or several) I'd make these for his birthday!
...moderators, if you feel this is in the wrong forum, please move as appropriate.