Castle of the Winds had a bank. You deposited all of your money there so that you didn't get weighed down by it. The bank didn't give you interest, but they gave you a "letter of credit", good within the town. Merchants could reclaim any purchases you made by withdrawing from your account. Come to think of it, it is a cheque book.
It could be tricky with multiple towns though. Where is most of your money kept? And when you move onto the wastelands, there goes all your hard earned cash.
In <img src="/ubbthreads/images/graemlins/div.gif" alt="" />, gold doesn't weigh anything.
