i made a creditcard for DXMP and it was VERY easy...
i made it because the original [A] funline ones made huge lag because of millions of little green things everywhere and the darkforce one you can only give 20 at a time...
basicaly its a weapon (crossbow re-meshed, with diff damage) that fire a dart (that looks like creditcard does 0 damge) that when hits a wall spawns 1 ammo of that credit type...
it starts off with 200 credits on $10 at time, when you find somthing on floor ...like, 100credits in one chit then pick it up and press ammo change with credcard to fire that 1 chit you just got,
shoot it on floor in front of someone and they pick up very simple and it has a small lifespan to stop lag-
only problem is you cant bank it...but it only uses one slot anyway
EDIT: o yea it fires chits of... 10 / 100 /and 1000 and do not fire directly at an actor because that chit'l be lost forever...