Prototype- vending machine

I've got my first big idea and I'm ready to jump in with my VISA card and a mock blueprint. It's time the world had a LEGO vending machine for minifigs. Ideally, I can figure out how to program it in order for the minifigs to be vended. In the very likely event that this proves to be beyond my limited programming and wiring skills, a static LEGO vending machine would be no less awesome.

At left, you see the prototype, it's definitively too boxy and the individual details are not articulated. However, it was built primarily from the Pick A Brick cup that I bought at the LEGO retail store while at Brickworld. Which, considering I didn't have a clue as to what I would do with that $15 cup of parts yesterday, makes me feel pretty good about how it turned out.

I built the prototype fairly quickly and in essentially two parts. The frame and left half are a single piece, while the windows and green base for the "vending display" portion of the machine was slotted into open space where it is held in place by the red border.

I think the next step is measuring vending machines and figuring out how to translate those measurements into a scale sculpture that feels right for vending minifigs. I'm excited by the potential for this project, although I could certainly use suggestions for parts.

Anybody have any ideas for dollar bill acceptors, change slots, and an alphabetized ordering system?