Nxt could have a special kind of asset backed by fixed amount of NXT.
But if we aren't supposed to "trade NXT" then that wouldn't have any value then would it?
The point is that we are NOT supposed to do anything, it's up to the community how to develop Nxt further.
I think it is best for NXT to have multiple purposes.
1 - As a store of value because of it's scarcity.
2 - As an intermediate currency between IOUs issued on the asset exchange.
IMO, of all things, NXT - as the base unit - is like gold. It backs up everything in the system because everything can be traded for it, the supply is constant, and its value (within the NXT ecosystem) is guaranteed by the protocol. EDIT: Plus, it makes sense, people don't use gold as currency (anymore) but it still has huge store of value.
And holy shit, why is NXT still tied to BTC... maybe we should contact coinbase to do USD/NXT pair
