Banking

Ok so I was planing on making a program that would handle all of the banking on the server. I was wondering if anyone had done this and if there was code, I don't mind starting from scratch but making the program from scratch would take longer.

Please let me know. and if you have suggestions on what to do or not to do that would help me out a lot Thanks

I have a couple suggestions, and some things to point out.
You should make sure to start the program in the "startup" file (preferably on a floppy in a disk drive) and have it CTRL+T proof, otherwise people could come in and edit the files to say they have millions of currency, when they really don't.
Also when nobody is around the area, the "chunk" (16x16 area) it is in will unload and make the computer shut off, so have it save often.
Make sure people can't place a disk drive around the computer (or put one behind or below it, keep the drive out of access though), because disk drives will override the computer's startup program, creating another backdoor.
Also make sure that you can still gain access to the console, if you need to for whatever reason (maybe Rednet signal).
I hope this helped, and I hope that you can get the program to work!

Thanks I may use world anchors at the server (making the system have to phone home so I can make multiple ATM's

If you do that, then make sure to take note of the distance restriction of wireless modems, if you intend to use them (bundled cables have no maximum distance, but they can take a while to get strung across the world).

Computercraft Wiki said:

Modems can send messages to other modems located up to 64 metres away, or 17 metres during a thunderstorm.

unless I change it in the server

modem_range=64