You are contradicting yourself. You state that it has no value because it cannot be used for anything, but you note that it does have a use! It has a use and that gives it value. If someone wants to trade with bitcoins, they must obtain bitcoins from someone else. That gives it value.

Your basic argument is based on the Mises Regression Theorem and there are two points to be made about that. First, the Theorem is not proven -- it is more of a generalization or a hypothesis. Second, the evidence for the Theorem is historical (and anecdotal), and that doesn't preclude a new currency from proving it wrong.