i think that I have understod you
as I have understod, it could be made out of somthing that will not go out
because when a user buys an item the money will go to that account and when a user looses an amount of money it will go also to that account.
if an administrator takes some money from a user if he made any mistake or any problem.
in my forum if users do any problem i will take money from them
or if you delete a topic or a reply it will also take money from user to that account.
and I can make the balance in the account very high so money will not go out.
I wish if that could be made and I think that it is not very difficult, it is almost the same like when u send money to another account or if a user buys an item from other user it will go to that user account.
CuTe_MaN