It would be great to have an opportunity to create additional currencies.
There also could be a way to exchange from one currency to another and have exchange rates in admin page:
eg:
___| A | B | C A | 1 | 29 | 493
B | 0.03 | 1 | 17
C | 0.002 | 0.05 | 1
Admin could decide in which currency bonuses should be given (eg. lowest currency for characters in message, largest currency for new topic, etc.)