Minifridge meets pedestal server

[EyeMWing]

So, we're nerds. We have two bigarsed pedestal servers that, because we don't have any hotswap HDDs that will work reliably, are doing nothing. Right now, they're acting as a stand for our minifridge, and nothing more.

Quad PPRo, 2gb of EDO RAM, these things are quite the monsters. Anyway, in our quest to make money and be even bigger nerds, we want to take one of these, and our minifridge, and make them into a vending machine. Even a simplistic vending machine that will just unlock the door of the fridge will work nicely. We have two potential modes of accepting credit - either a bill/coin acceptor (it would have to be both, unfortunately), or a simpler method would be a simple PS/2 mag-strip reader to allow authorized personnel (i.e. people who we can trust to pay, or take payment) to open the fridge with their ID badges.

Additionally, this can't cost more than a few dollars. Programming is no problem - we can do anything but ASM.

 

[Heisenberg]

It shouldn't be that hard. You could probably use a serial port for the I/O stuff. I'd probably use a solenoid for the actual locking mechanism, and fab up a couple pieces of metal to use with it.

 

[cheesehead]

I'll trade one of the servers for an Atmel or PIC microcontroller kit. (Seriously, I would'nt mind owning one of those, if only for an awesome coffee table.)

Seriously, though, a microcontroller would be the way to go. All you need to do is wire it to a keypad, such as that which can be had by gutting an old telephone. Set 0 for a "reset" switch, and the other 9 for entering the code. (The PIC16f877a, which is about 7$, has roughly 30 line of i/o.) You could also connect it via RS232, if you wanted.
http://www.kmitl.ac.th/~kswichit/easyserver0.9/easyserver0.9.htm